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1.
J Healthc Eng ; 2022: 7315665, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35591941

RESUMO

Accurate preoperative glioma grading is essential for clinical decision-making and prognostic evaluation. Multiparametric magnetic resonance imaging (mpMRI) serves as an important diagnostic tool for glioma patients due to its superior performance in describing noninvasively the contextual information in tumor tissues. Previous studies achieved promising glioma grading results with mpMRI data utilizing a convolutional neural network (CNN)-based method. However, these studies have not fully exploited and effectively fused the rich tumor contextual information provided in the magnetic resonance (MR) images acquired with different imaging parameters. In this paper, a novel graph convolutional network (GCN)-based mpMRI information fusion module (named MMIF-GCN) is proposed to comprehensively fuse the tumor grading relevant information in mpMRI. Specifically, a graph is constructed according to the characteristics of mpMRI data. The vertices are defined as the glioma grading features of different slices extracted by the CNN, and the edges reflect the distances between the slices in a 3D volume. The proposed method updates the information in each vertex considering the interaction between adjacent vertices. The final glioma grading is conducted by combining the fused information in all vertices. The proposed MMIF-GCN module can introduce an additional nonlinear representation learning step in the process of mpMRI information fusion while maintaining the positional relationship between adjacent slices. Experiments were conducted on two datasets, that is, a public dataset (named BraTS2020) and a private one (named GliomaHPPH2018). The results indicate that the proposed method can effectively fuse the grading information provided in mpMRI data for better glioma grading performance.


Assuntos
Glioma , Imageamento por Ressonância Magnética Multiparamétrica , Glioma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Gradação de Tumores , Redes Neurais de Computação
2.
Int J Biol Macromol ; 124: 1205-1212, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30521905

RESUMO

In this research, collagen hydrolysates with different average molecular weights (Mn¯) from leather collagen were chosen as raw materials. Five environmental-friendly sizing agents (SA) were prepared by cross-linking collagen hydrolysates with glycol diglycidyl ether (GDE) and further grafting them with butyl acrylate (BA) and styrene (St). Then the compound sizing agents (SGDESA-x, x = 1, 2, 3 and 4) were obtained by simple physical mixing of GDESA and starch. The surface sizing performance of GDESA and compound sizing agents were studied. The research result shows that both physical, mechanical properties and water resistance of the corrugated paper coated by GDESA were significantly improved when Mn¯ of collagen hydrolysate was about 10,000, and its emulsion exhibited robust stability in long standing time. Furthermore, when the SGDESA-2 was used as a sizing agent, the coated corrugated paper exhibited strong water resistance, good physical and mechanical properties even after refolded for 20 times.


Assuntos
Colágeno/química , Reagentes de Ligações Cruzadas/química , Resinas Epóxi/química , Papel , Hidrolisados de Proteína/química , Acrilatos/química , Animais , Colágeno/isolamento & purificação , Humanos , Indústria Manufatureira/métodos , Teste de Materiais , Hidrolisados de Proteína/isolamento & purificação , Pele/química , Amido/química , Estireno/química , Resíduos
3.
Polymers (Basel) ; 10(1)2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30966110

RESUMO

In order to improve the dispensability of graphene oxide (GO) in waterborne polyurethane (WPU), sulfonated graphene (SGO) with superior dispersity was prepared by modifying graphene oxide with sodium 2-chloroethane sulfonate to introduce hydrophilic sulfonic groups into the structure. SGO/WPU composites were prepared using isophorone diisocyanate (IPDI), polytetramethylene ether glycol (PTMEG 2000), dimethylolpropionic acid (DMPA) and SGO as raw materials. The influence of SGO content on composite properties were investigated. The structure and morphology of SGO and SGO/WPU composites were characterized by infrared spectroscopy, X-ray diffractometry and transmission electron microscopy etc. Their mechanical properties and wear resistance were analyzed as well. The experimental results showed that SGO was successfully grafted onto polyurethane macromolecule by an in situ method and, with the introduction of sulfonic groups, the interfacial compatibility of GO and PU was improved significantly so that SGO evenly dispersed into WPU. The SGO that was grafted onto WPU macromolecules exhibited layered morphology with nanometers in the WPU matrix. With increasing SGO content, the tensile strength and the wear resistance of the film increased, but the addition of more than 0.8 wt % SGO yielded unfavorable results. When the added amount of SGO was 0.8 wt % of WPU, the tensile strength of the composite film was 46.53% higher than that of the blank group, and the wear resistance of the film was remarkably improved, which was due to a strong interaction between the SGO and WPU phases. Thus, the conclusion can be drawn that appropriate amount of SGO addition can enhance the mechanical properties of SGO/WPU composite film.

4.
Opt Express ; 25(2): 1288-1295, 2017 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-28158012

RESUMO

With the classical ensemble method, the correlated-electron dynamics of Mg atom from a doubly excited, transition Coulomb complex in few-cycle circularly polarized (CP) laser field at low laser intensity is theoretically investigated. The low energy transfer during the recollision process indicates that the two electrons cannot release directly, but it can pass through a doubly excited state, and then escape with the ionization time difference. The numerical results show that the feature of the sequential double ionization (SDI) can be observed in the nonsequential double ionization (NSDI) process. The SDI-like results demonstrate that the intermediate state has lost any memory of its formation dynamics. The distribution of the angle between the two release directions of the two electrons also depends on the ionization time difference. Finally, the influence of e-e Coulomb repulsion is discussed.

5.
J Agric Food Chem ; 65(1): 104-116, 2017 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-27977187

RESUMO

The surfactants of the linear-hyperbranched phosphate esters (PAMAMGn-3-Ps) have been constructed through random multibranching esterification of lauroyl chloride and phosphate ester as a branching agent. Subsequently, a series of surfactant products were obtained. Benefiting from the amphiphilic structure with the hydrophilic core and many hydrophobic tails, PAMAMGn-3-Ps were able to self-assemble into nanomicelles in aqueous media. Importantly, the polymers show low critical micelle concentrations (CMCs) and small particle sizes. Here, PAMAMG1-3-P was applied in the collagen fibers of leather to improve the fibers' distance and mechanical property of collagen fibers. Additionally, the polymers display significant flexibility, which could replace ordinary fatliquor in the future. The result provides a new application of using linear-hyperbranched amphiphilic phosphate esters into traditional leather materials to enhance the performance of collagen fibers.


Assuntos
Colágeno/química , Ésteres/química , Fosfatos/química , Interações Hidrofóbicas e Hidrofílicas , Micelas , Tamanho da Partícula , Polímeros/química , Tensoativos
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