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Toughening the petroleum-based epoxy resin blends with bio-based modifiers without compromising their modulus, mechanical strength, and other properties is still a big challenge in view of the sustainability. In this study, a bio-based liquid crystal epoxy resin (THMT-EP) with an s-triazine ring structure was utilized to modify a petroleum-based bisphenol A epoxy resin (E51) with 4,4′-diaminodiphenylsulfone (DDS) as a curing agent, and the blended systems were evaluated for their thermal stability, mechanical properties, and flame retardancy. The results showed that the impact strength of the blended system initially increased and then decreased with the increase in THMT-EP content, and it reached the a maximum value of 26.5 kJ/m2 when the THMT-EP content was 5%, which was 31.2% higher than that of E51/DDS. Notably, the flexural strength, modulus, and glass transition temperature of the blended system were all simultaneously improved with the addition of THMT-EP. At the same time, the addition of THMT-EP enhanced the flame retardancy of the system by increasing the char yield at 700 °C and decreasing the peak heat release rate and total heat release rate. This work paves the way for a more sustainable improvement in the comprehensive performance of epoxy resin. [ABSTRACT FROM AUTHOR]

The aim of this study is to propose a new diagnostic model based on "segmentation + classification" to improve the routine screening of Thyroid nodule ultrasonography by utilizing the key domain knowledge of medical diagnostic tasks. A Multi-scale segmentation network based on a pyramidal pooling structure of multi-parallel void spaces is proposed. First, in the segmentation network, the exact information of the underlying feature space is obtained by an Attention Gate. Second, the inflated convolutional part of Atrous Spatial Pyramid Pooling (ASPP) is cascaded for multiple downsampling. Finally, a three-branch classification network combined with expert knowledge is designed, drawing on doctors' clinical diagnosis experience, to extract features from the original image of the nodule, the regional image of the nodule, and the edge image of the nodule, respectively, and to improve the classification accuracy of the model by utilizing the Coordinate attention (CA) mechanism and cross-level feature fusion. The Multi-scale segmentation network achieves 94.27%, 93.90% and 88.85% of mean precision (mPA), Dice value (Dice) and mean joint intersection (MIoU), respectively, and the accuracy, specificity and sensitivity of the classification network reaches 86.07%, 81.34% and 90.19%, respectively. Comparison tests show that this method outperforms the U-Net, AGU-Net and DeepLab V3+ classical models as well as the nnU-Net, Swin UNetr and MedFormer models that have emerged in recent years. This algorithm, as an auxiliary diagnostic tool, can help physicians more accurately assess the benign or malignant nature of Thyroid nodules. It can provide objective quantitative indicators, reduce the bias of subjective judgment, and improve the consistency and accuracy of diagnosis. Codes and models are available at https://github.com/enheliang/Thyroid-Segmentation-Network.git [ABSTRACT FROM AUTHOR]

Tensorized type-2 single layer feedforward network extends the single layer feedforward network with tensorized type-2 fuzzy structure. In the tensorized type-2 single layer feedforward network, type-2 fuzzy sets are used to generate tensor with lower membership function, principal membership function and upper membership function. Other compositions of the single layer feedforward network, such as defuzzification results, weighted averaged results and different type reduction results could also be formed by the tensorized fuzzy construction method. In thus doing, the type-reduction or defuzzification approach is the unimportance procedure in the fuzzy network operation and construction. To deeply unveil the implicit information hidden in the type-2 fuzzy sets, cross-shaped convolution with irregular convolution kernel is used to form the tensor. The named irregular convolution kernel based tensorized type-2 single layer feedforward network adopts an iterative tensor equation solving algorithm with tensor inequality constraint (Huang and Ma in Linear Multilinear Algebra, 1–24, 2021, https://doi.org/10.1080/03081087.2021.1954140). Finally, the effectiveness of different convolution kernels for irregular convolution strategy based tensorized type-2 single layer feedforward network are tested. Comparisons are carried out on several benchmark datasets, and five different type-reduction methods for the irregular convolution strategy based tensorized type-2 single layer feedforward network are compared. Results show that the proposed learning method could be improved with this new information extraction strategy. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study explored the role of P2X7 receptors in spinal cord astrocytes in the electroacupuncture-induced inhibition of visceral hypersensitivity (VH) in rats with irritable bowel syndrome (IBS). Visceral hypersensitivity of IBS was intracolonically induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). Visceromotor responses to colorectal distension (CRD-20,40,60,80 mmHg) and abdominal withdrawal reflex scoring (AWRs) were recorded after electroacupuncture at bilateral Zusanli (ST36) and Sanyinjiao (SP6) acupoints to evaluate the analgesic effect of electroacupuncture on visceral pain in rats with IBS. Fluorocitric acid (FCA), an astrocyte activity inhibitor, was injected intrathecally before electroacupuncture intervention and AWRs were recorded. Western blot and real-time qPCR were used to detect the expression of NMDA and P2X7 receptor to observe the regulation effect of electroacupuncture on NMDA receptor in the spinal cord of rats with visceral hypersensitivity. Intrathecal injection of P2X7 agonist or antagonist was administered before electroacupuncture treatment. To observe the effect of P2X7 receptor in spinal astrocytes on the inhibition of visceral hyperalgesia by electroacupuncture, the changes of AWR score, NMDA receptor in the spinal cord, and GFAP expression in astrocytes were detected. Inflammation of the colon had basically subsided at day 21 post-TNBS; persistent visceral hypersensitivity could be suppressed by electroacupuncture. This analgesic effect could be inhibited by FCA. The analgesic effect, downregulation of NMDA receptor NR1 subunit, and P2X7 protein of electroacupuncture were all reversed by FCA. P2X7 receptor antagonist A740003 can cooperate with EA to carry out analgesic effect in rats with visceral pain and downregulate the expression of NR1, NR2B, and GFAP in spinal dorsal horn. However, the P2X7 receptor agonist BzATP could partially reverse the analgesic effect of EA, inhibiting the downregulatory effect of EA on the expression of NR1, NR2B, and GFAP. These results indicate that EA may downregulate the expression of the NMDA receptor by inhibiting the P2X7 receptor in the spinal cord, thereby inhibiting spinal cord sensitization in IBS rats with visceral pain, in which astrocytes are an important medium. [ABSTRACT FROM AUTHOR]

The incidence of thyroid nodules is increasing year by year. Accurate determination of benign and malignant nodules is an important basis for formulating treatment plans. Ultrasonography is the most widely used methodology in the diagnosis of benign and malignant nodules, but diagnosis by doctors is highly subjective, and the rates of missed diagnosis and misdiagnosis are high. To improve the accuracy of clinical diagnosis, this paper proposes a new diagnostic model based on deep learning. The diagnostic model adopts the diagnostic strategy of localization-classification. First, the distribution laws of the nodule size and nodule aspect ratio are obtained through data statistics, a multiscale localization network structure is a priori designed, and the nodule aspect ratio is obtained from the positioning results. Then, uncropped ultrasound images and nodule area image are correspondingly input into a two-way classification network, and an improved attention mechanism is used to enhance the feature extraction performance. Finally, the deep features, the shallow features, and the nodule aspect ratio are fused, and a fully connected layer is used to complete the classification of benign and malignant nodules. The experimental dataset consists of 4021 ultrasound images, where each image has been labeled under the guidance of doctors, and the ratio of the training set, validation set, and test set sizes is close to 3:1:1. The experimental results show that the accuracy of the multiscale localization network reaches 93.74%, and that the accuracy, specificity, and sensitivity of the classification network reach 86.34%, 81.29%, and 90.48%, respectively. Compared with the champion model of the TNSCUI 2020 classification competition, the accuracy rate is 1.52 points higher. Therefore, the network model proposed in this paper can effectively diagnose benign and malignant thyroid nodules. [ABSTRACT FROM AUTHOR]

Objective: To explore whether acupuncture combined with moxibustion could inhibit epithelialmesenchymal transition in Crohn's disease by affecting the transforming growth factor β 1 (TGF- β 1)/Smad3/Snail pathway. Methods: Sixty-three patients with Crohn's disease were randomly divided into an observation group (31 cases) receiving moxibustion at 43 °C combined with acupuncture, and a control group (32 cases) receiving moxibustion at 37 °C combined with sham acupuncture using a random number table. Patients were treated for 12 weeks. Crohn's Disease Activity Index (CDAI) was used to evaluate disease activity. Hematoxylin-eosin staining and transmission electron microscopy were utilized to observe the morphological and ultrastructural changes. Immunohistochemistry was used to detect the expression of transforming growth factor β 1 (TGF-β 1), T β R1, T β R2, Smad3, Snail, E-cadherin and fibronectin in intestinal mucosal tissues. Results: The decrease of the CDAI score, morphological and ultrastructural changes were more significant in observation group. The expression levels of TGF- β 1, Tβ R2, Smad3, and Snail in the observation group were significantly lower than those before the treatment (P<0.05 or P<0.01). After treatment, the expression levels of TGF-β 1, TβR2, and Snail in the observation group were significantly lower than those in the control group (all P<0.05); compared with the control group, the expression of fibronectin in the observation group was significantly decreased, and the expression of E-cadherin was significantly increased (all P<0.05). Conclusions: Moxibustion at 43 °C combined with acupuncture may suppress TGF-β 1/Smad3/Snail pathway-mediated epithelial-mesenchymal transition of intestinal epithelial cells in Crohn's disease patients by inhibiting the expression levels of TGF-β 1, Tβ R2, Smad3, and Snail. (Registration No. ChiCTR-IIR-16007751) [ABSTRACT FROM AUTHOR]

This paper investigates the distributed cooperative learning (DCL) from adaptive neural network (NN) control for a group of strict-feedback systems, where the structure of all strict-feedback systems is identical. In order to achieve DCL easily, the system transformation method is employed for the strict-feedback systems. For an agent, only one radial basis function NN is used to approximate the lumped uncertainty in control design. Then the output tracking performance of all strict-feedback systems is guaranteed. What's more, we prove that weights of all NNs in a multi-agent system converge to a small neighborhood around their common optimal value if the topology of the multi-agent system is connected and undirected. Thus, the approximation domain of all NNs is enlarged. Further, the previous learned NNs are used to improve the control performance. Finally, we provide two examples to demonstrate the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Let {(ξni, ηni), 1 ≤ i ≤ n, n ≥ 1} be a triangular array of independent bivariate elliptical random vectors with the same distribution function as (S1,ρnS1+1−ρn2S2),ρn∈(0,1), where (S1, S2) is a bivariate spherical random vector. For the distribution function of radius S12+S22 belonging to the max-domain of attraction of the Weibull distribution, the limiting distribution of maximum of this triangular array is known as the convergence rate of ρn to 1 is given. In this paper, under the refinement of the rate of convergence of ρn to 1 and the second-order regular variation of the distributional tail of radius, precise second-order distributional expansions of the normalized maxima of bivariate elliptical triangular arrays are established. [ABSTRACT FROM AUTHOR]

This study aims to explore the efficacy of interferon-α (IFN-α) combined with either entecavir (ETV) or adefovir (ADV) therapy versus IFN-α mono-therapy for chronic hepatitis B (CHB) patients, and to identify the factors associated with treatment outcomes. Totally, 159 CHB patients receiving interferon-based treatment for 48 weeks were enrolled in this retrospective study, including IFN-α mono-therapy group (group A, n=44), IFN-α plus ADV group (group B, n=53) and IFN-α plus ETV group (group C, n=62). The primary measures of efficacy assessments were the changes in HBsAg. Cox regression analysis was used to identify the predictors of treatment outcomes. The predictive values of the factors were assessed by ROC analysis. For patients with baseline hepatitis B surface antigen (HBsAg) level <1000 IU/mL, the reductions in mean HBsAg levels at week 48 were greater in group C than that in group A ( P<0.05). Higher rate of HBeAg seroconversion was achieved in the combined therapy group than in IFN-α mono-therapy group at week 48 ( P<0.05). Two factors were independently associated with HBeAg seroconversion: baseline HBeAg level <2.215 log10 index/mL and ΔHBeAg (decline in HBeAg from baseline) >0.175 log10 at week 12. In conclusion, interferon-α plus ETV therapy can accelerate HBsAg decline as compared with interferon-α mono-therapy in CHB patients with lower baseline HBsAg levels, and the combination therapy was superior to IFN-α mono-therapy in increasing the rate of HBeAg seroconversion. Baseline HBeAg and ΔHBeAg at week 12 can independently predict HBeAg seroconversion in patients subject to interferon-based therapy for 48 weeks. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we study the joint limit distributions of point processes of exceedances and partial sums of multivariate Gaussian sequences and show that the point processes and partial sums are asymptotically independent under some mild conditions. As a result, for a sequence of standardized stationary Gaussian vectors, we obtain that the point process of exceedances formed by the sequence (centered at the sample mean) converges in distribution to a Poisson process and it is asymptotically independent of the partial sums. The asymptotic joint limit distributions of order statistics and partial sums are also investigated under different conditions. [ABSTRACT FROM AUTHOR]

The effect of ammonium sulfamate (AS) content on the flame retardancy of polyamide 6 (PA6) was studied. It is found that the limiting oxygen index (LOI) of PA6 increases with the increase of AS content and the flame retardancy of PA6 is significantly improved. The morphology of the residues after combustion was examined by means of scanning electron microscopy (SEM). SEM results show that AS facilitates the formation of the intumescent char layer with honeycomb-like structure, which inhibits the transfer of heat and mass, and thus improves the flame retardancy of PA6. The thermal degradation of AS flame retarded PA6 was studied by thermogravimetric analysis (TGA). The Kissinger method was applied to estimate the activation energy ( Ea) of the degradation. The activation energy of the thermal degradation of PA6 decreases by adding AS, indicating that AS can promote the degradation of PA6. [ABSTRACT FROM AUTHOR]

ylonitrile/ N-[4-(aminosulfonyl)phenyl]acrylamide (AN/ASPAA) copolymers were synthesized and used as a host of lithium ion conducting electrolytes. The composition, molecular weight and molecular weight distribution of AN/ASPAA copolymers were determined, and the influence of copolymer composition on the glass temperature of AN/ASPAA copolymers and the ion conductivity of electrolytes were investigated. The molecular weights of AN/ASPAA copolymers were lower than those of AN and ASPAA homopolymers due to the cross-termination reaction. The glass temperatures of AN/ASPAA copolymers increased as the molar fraction of ASPAA units in copolymers increased. The lithium ion conductivities of the polymer electrolytes increased initially as the molar fraction of ASPAA units in copolymers increased, and a maximum conductivity was achieved when the molar fraction of ASPAA in the copolymer was 16.8%. [ABSTRACT FROM AUTHOR]

The effect of N,N,N′N′-tetraalkyl terephthalamide (TATA) on the crystallization of polypropylene (PP) was studied by means of differential scanning calorimetry, wide angle X-ray diffraction and polarized optical microscopy. It was found that the addition of TATA effectively induced the formation of β-crystalline form of PP. With the increase of TATA content both the total crystallinity degree ( x) and crystallinity degree for β-crystalline form ( x β) of PP increased significantly, while the crystallinity degree for α-crystalline form ( x α) decreased. Polarized optical micrographs indicated that the addition of TATA led to a substantial decrease in the size of spherulites of PP and the boundaries of spherulites were hardly distinguished. TATA could significantly improve the impact strength, flexural strength and modulus of PP, while the tensile strength of PP did not change greatly with TATA content. [ABSTRACT FROM AUTHOR]