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Impact of Carbon Chain Structures in the Backbone on the Flexibility of Modified Polyarylene Sulfide Resins: Molecular Dynamics Simulations and Mesoscopic Analysis

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chinese Journal of Polymer Science 2024年第4期42卷 544-557页

作者： chi Zhang Rong Liu jing-Yuan Liu Wen-Wei Jiang Key Laboratory of Fine Chemical Engineering and Functional Materials School of Chemical EngineeringSichuan UniversityChengdu610065China

In the domain of high-performance engineering polymers, the enhancement of mechanical flexibility in poly(phenylene sulfide) (PPS) resins has long posed a significant challenge. A novel molecular structure, designated as PP-He-IS, wherein imide rings and an aliphatic hexylene chain are covalently incorporated into the PPS backbone to enhance its flexibility, is introduced in this study. Molecular dynamics (MD) simulations are employed to systematically explore the effects of diversifying the backbone chain structures by substituting phenyl units with alkyl chains of varying lengths, referred to as PP-A-IS where “A” signifies the distinct intermediary alkyl chain configurations. Computational analyses reveal a discernable decrement in the glass transition temperature (Tg) and elastic modulus, counterbalanced by an increment in yield strength as the alkyl chain length is extended. Notably, the PP-He-IS variant is shown to exhibit superior yield strength while simultaneously maintaining reduced elastic modulus and Tg values, positioning it as an advantageous candidate for flexible PPS applications. Mesoscopic analyses further indicate that structures such as PP-He-IS, PP-Pe-IS, and PP-Bu-IS manifest remarkable flexibility, attributable to the presence of freely rotatable carbon-carbon single bonds. Experimental validation confirms that a melting temperature of 504 K which is lower than that of conventional PPS, and lower crystallinity are exhibited by PP-He-IS, thereby affording enhanced processability without compromising inherent thermal stability. Novel insights into the strategic modification of PPS for mechanical flexibility are thus furnished by this study, which also accentuates the pivotal role played by molecular dynamics simulations in spearheading high-throughput investigations in polymer material modifications.

关键词： Molecular dynamics simulations Polyarylene Sulfide Main-chain modifications Flexibility Aliphatic hexylene chain

Differential Evolution Hemivariational Inequalities with Anti-periodic Conditions

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1143-1160页

作者： jing ZHAO Chun Mei GAN zhen Hai LIU School of Mathematics and Quantitative Economics Guangxi University of Finance and EconomicsNanning 530003P.R.China Guangxi Colleges and Universities Key Laboratory of Optimization Control and Engineering Calculation Guangxi Minzu UniversityNanning 530006P.R.China

The goal of this paper is to deal with a new dynamic system called a differential evolution hemivariational inequality(DEHVI)which couples an abstract parabolic evolution hemivariational inequality and a nonlinear differential equation in a Banach space.First,by apply ing surjectivity result for pseudomonotone multivalued mappins and the properties of Clarke's subgradient,we show the nonempty of the solution set for the parabolic hemivariational inequality.Then,some topological properties of the solution set are established such as boundedness,closedness and convexity.Furthermore,we explore the upper semicontinuity of the solution mapping.Finally,we prove the solution set of the system(DEHVI)is nonempty and the set of all trajectories of(DEHVI)is weakly compact in C(I,X).

关键词： Differential parabolic hemivariational inequality Clarke subdifferential hyperbolicparabolic system parabolic-parabolic system existence result

A data-driven approach to RUL prediction of tools

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Advances in Manufacturing 2024年第1期12卷 6-18页

作者： Wei Li Liang-chi Zhang Chu-Han Wu Yan Wang zhen-Xiang Cui Chao Niu Department of Mechanical Engineering University College LondonLondonWC1E 7JEUK Shenzhen Key Laboratory of Cross-Scale Manufacturing Mechanics Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China SUSTech Institute for Manufacturing Innovation Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China School of Mechanical and Manufacturing Engineering The University of New South WalesKensingtonNSW2052Australia Baoshan Iron&Steel Co. Ltd.Shanghai200941People’s Republic of China

An effective and reliable prediction of the remaining useful life(RUL)of a tool is important to a metal forming process because it can significantly reduce unexpected maintenance,avoid machine shutdowns and increase system stability.This study proposes a new data-driven approach to the RUL prediction for metal forming processes under multiple contact sliding conditions.The data-driven approach took advantage of bidirectional long short-term memory(BLSTM)and convolutional neural networks(CNN).A pre-trained lightweight CNN-based network,WearNet,was re-trained to classify the wear states of workpiece surfaces with a high accuracy,then the classification results were passed into a BLSTM-based regression model as inputs for RUL estimation.The experimental results demonstrated that this approach was able to predict the RUL values with a small error(below 5%)and a low root mean square error(RMSE)(around 1.5),which was more superior and robust than the other state-of-the-art methods.

关键词： Remaining useful life(RUL) Bidirectional long short-term memory(BLSTM) Data-driven approach Metal forming

Precision medicine in inflammatory bowel disease

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Precision Clinical Medicine 2024年第1期7卷 54-80页

作者： zhen Zeng Mingshan Jiang Xi Li jing Yuan Hu Zhang Department of Gastroenterology West China HospitalSichuan UniversityChengdu 610041China Centrefor Inflammatory Bowel Disease West China HospitalSichuan UniversityChengdu 610041China Lab of Inflammatory Bowel Disease Frontiers Science Center for Disease-Related Molecular NetworkWest China HospitalSichuan UniversityChengdu 610041China General Practice Ward/International Medical Center Ward General Practice Medical CenterWest China HospitalSichuan UniversityChengdu 610041China

Inflammatory bowel disease(IBD)is an incurable disease characterized by remission-relapse cycles throughout its course.Both Crohn's disease(CD)and ulcerative colitis(UC),the two main forms of IBD,exhibit tendency to develop complications and substantial heterogeneity in terms of frequency and severity of relapse,thus posing great challenges to the clinical management for IBD.Current treatment strategies are effective in different ways in induction and maintenance therapies for IBD.Recent advances in studies of genetics,pharmacogenetics,proteomics and microbiome provide a strong driving force for identifying molecular markers of prognosis and treatment response,which should help clinicians manage IBD patients more effectively,and then,improve clinical outcomes and reduce treatment costs of patients.In this review,we summarize and discuss precision medicine in IBD,focusing on predictive markers of disease course and treatment response,and monitoring indices during therapeutic drug monitoring.

关键词： disease course inflammatory bowel disease precision treatment precision monitoring treatment response

Doping engineering of iron oxide nanoparticles towards high performance and biocompatible T_(1)-weighted MRI contrast agents

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Rare Metals 2024年第1期43卷 298-308页

作者： Xue Xu Ping-Li Dong Yu-Yun Chai Run Yang zhen-Hui Ma chi-Chong Lu Department of Chemistry College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityBeijing 100048China Department of Physics Beijing Technology and Business UniversityBeijing 100048China

Extremely small-sized iron oxide nanoparticles(IONPs) are of great interest in magnetic resonance imaging(MRI) due to their biosafety as an alternative to clinical gadolinium(Ⅲ) complexes-based contrast agents.Especially when the particle size is less than 10 nm,it has strong diffusion ability and deep penetration distance in tumor tissue.Substitution doping can significantly enhance the T_(1)contrast effect of nanoparticles by regulating the surface exposed atoms.However,the nucleation and growth processes of multi-component synthesis systems are complex and difficult to be accurately controlled,leading to great challenges in the synthesis of ultra-small-sized nanoparticles with different components and sizes.Here,extremely smallsized superparamagnetic gadolinium-doped iron oxide nanoparticles(GdIONPs,Gd_(x)Fe_(3-x)O_(4) NPs) with adjustable doping amount and controllable size in the range of 3.5-7.5 nm were synthesized by thermal decomposition.Then,as-synthesized GdIONPs were surface modified with a highly water-soluble and biocompatible carboxyl-polyethylene glycol-phosphoric acid ligand with high binding affinity.Gd_(0.65)Fe_(2.35)O_(4) NPs exhibited very high r_(1) relaxivity of 10.6 mmol^(-1)·L·s^(-1) in terms of all metal concentrations and 49.0 mmol^(-1)·L·s^(-1) in terms of gadolinium alone,respectively,3 and 14 times higher than clinical T_(1) contrast agents(Gd-DTPA).GdIONPs can continuously obtain high resolution images of blood vessels,and can be used as an efficient and multifunctional contrast agent for MR T_(1)imaging.This stable and efficient doping strategy provides an easy and effective method to individually optimize the magnetic properties of complex oxides and their relaxation effects for a variety of biomedical applications.

关键词： Iron oxide nanoparticles Small size Magnetic resonance imaging Substitutional doping Gd dopant

Nitro-oleic acid ameliorates erectile dysfunction in a streptozotocin-induced rat model of diabetes by inhibiting oxidative stress and apoptosis and activating the NO/cGMP pathway

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Asian Journal of Andrology 2024年第1期26卷 57-66页

作者： Chang-Bo Zhao Wei-Bo Chen Wen-zhen Wang Fang-Xin Gong Cui-Qin Fan Ye Li Tian Lan Wen-jing Wang Ming-zhen Yuan Department of Urology Shandong Provincial HospitalShandong UniversityJinan 250012China Department of Andrology Liaocheng People's HospitalShandong UniversityLiaocheng 252000China Department of Urology The Second Hospital of Shandong UniversityJinan 250012China Department of Physiology School of Basic Medical SciencesShandong UniversityJinan 250012China

The major vascular complications associated with diabetes make the management of diabetic mellitus erectile dysfunction(DMED)a challenging endeavor.Notable factors contributing to DMED include oxidative stress,nitric oxide(NO)/cyclic guanosine monophosphate(cGMP)pathway activation,and apoptosis,while nitro-oleic acid(NO,-OA)has been shown to be beneficial in treating these aspects of this condition.We,herein,investigated the effects and possible mechanisms of NO,-OA on erectile function as assessed in a streptozotocin-induced rat model of diabetes.Our results revealed that the erectile function of DMED rats was significantly impaired compared with that of the control group.However,in response to 4 weeks of NO,-OA treatment,there was an improvement in erectile function.The expression of oxidative stress-related indicators was significantly increased and the NO/cGMP pathway was impaired in the DMED group.The expression of proapoptotic factors was increased,while that of antiapoptotic factors was decreased in the DMED group.Moreover,the cell morphology in the cavernous tissue of the DMED group also changed adversely.NO,-OA treatment significantly reversed all these changes observed in the DMED group.In conclusion,NO,-OA treatment partially improved erectile function in DMED rats through mechanisms that included inhibition of oxidative stress,activation of the NO/cGMP pathway,and a reduction in apoptosis.

关键词： apoptosis diabetic mellitus erectile dysfunction nitro-oleic acid NO/cGMP pathway oxidative stress

Prognostic value of circulating tumor cells combined with neutrophil-lymphocyte ratio in patients with hepatocellular carcinoma

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 372-385页

作者： Jia-Li Chen Lu Guo zhen-Ying Wu Kun He Han Li chi Yang Yun-Wei Han Department of Oncology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Ophthalmology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Clinical Research Institute The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Plastic Surgery Meguiar's Medical Beauty HospitalChengdu 610000Sichuan ProvinceChina

BACKGROUND Circulating tumor cell(CTC)count and neutrophil-to-lymphocyte ratio(NLR)are both closely associated with the prognosis of hepatocellular carcinoma(HCC).AIM To investigate the prognostic value of combining these two indicators in HCC.METHODS Clinical data were collected from patients with advanced HCC who received im-mune therapy combined with targeted therapy at the Department of Oncology,the Affiliated Hospital of Southwest Medical University,Sichuan,china,from 2021 to 2023.The optimal cutoff values for CTC programmed death-ligand 1(PD-L1)(+)>1 or CTC PD-L1(+)≤1 and NLR>3.89 or NLR≤3.89 were evaluated using X-Tile software.Patients were categorized into three groups based on CTC PD-L1(+)counts and NLR:CTC-NLR(0),CTC-NLR(1),and CTC-NLR(2).The relationship between CTC-NLR and clinical variables as well as survival rates was assessed.RESULTS Patients with high CTC PD-L1(+)expression or NLR at baseline had shorter median progression-free survival(m-PFS)and median overall survival(mOS)than those with low levels of CTC PD-L1(+)or NLR(P<0.001).Mean-while,patients in the CTC-NLR(2)group showed a significant decrease in mPFS and mOS.Cox regression analysis revealed that alpha-fetoprotein(AFP),CTC PD-L1(+),and CTC-NLR were independent predictors of OS.The time-dependent receiver operating characteristic curve showed that the area under the curve of CTC-NLR at 12 months(0.821)and 18 months(0.821)was superior to that of AFP and CTC PD-L1(+).CONCLUSION HCC patients with high CTC PD-L1(+)or NLR expression tend to exhibit poor prognosis,and a high baseline CTC-NLR score may indicate low survival.CTC-NLR may serve as an effective prognostic indicator for patients with advanced HCC receiving immunotherapy combined with targeted therapy.

关键词： Circulating tumor cells Neutrophil–lymphocyte ratio Hepatocellular carcinoma Prognosis Survival Marker

Manipulation of magnetocaloric and elastocaloric effects in Ni-Mn-In alloys by lattice volume and magnetic variation:Effect of Co and Fe co-doping

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Journal of Materials Science & Technology 2024年第5期172卷 156-165页

作者： Xinzeng Liang chi Zhang jing Bai Jianglong Gu Yudong Zhang Claude Esling Xiang Zhao Liang Zuo School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Key Laboratory for Anisotropy and Texture of Materials Northeastern UniversityShenyang 110819China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Laboratoire d’Étude des Microstructures et de Mécanique des Matériaux LEM3 CNRSUMR 7239University of Lorraine57045 MetzFrance

The effects of Co and Fe co-doping Ni-Mn-In alloy on the phase stability,lattice parameters,mag-netic properties,and electronic structures are systematically investigated by using the first-principles calculations.Results indicate that Fe atoms replace the excess Mn2 atoms by direct and indirect coex-istence(Fe→Mn 2 and Fe→In→Mn2);Co substitutes the Ni atoms by direct substitution(Co→Ni)for the Ni-Mn-In alloy.The austenites all exhibit the ferromagnetic(FM)state for the studied composi-tions.The NM martensites are in the ferrimagnetic(FIM-1)state for the Ni_(2)Mn_(1.5)In_(0.5),Ni_(2)Mn_(1.25)In_(0.5)Fe 0.25,Ni_(1.75)Mn_(1.5)In_(0.5)Co_(0.25),and Ni_(1.75)Mn_(1.25)In_(0.5)Co_(0.25)Fe 0.25 alloys,while the other compositions are in the FM state.The phase stability of austenite and martensite decreases with increasing Co and Fe co-doping.A magnetic-structural coupling transition occurs at x<0.25 and y<0.25.The Ni_(1.91)Mn_(1.5)In_(0.5)Co_(0.08)and Ni_(1.91)Mn_(1.42)In_(0.5)Co_(0.08)Fe_(0.08)alloys exhibit an A→6M→NM transformation,accompanied by a magnetic transition.When Co and Fe are co-doped,the hybridization strength between Co and Fe is greater than that between Co/Fe and Mn.The enhancement of magnetocaloric and elastocaloric effects is favored by larger magnetization difference(△M)and lattice volume change(△V/V_(0)).Based on the calculated phase stability,magneto-structure coupling,△V/V 0 and c/a ratio,one can predict that the Ni_(2)-x Mn_(1.5)-y In_(0.5)Co x Fe y alloy with Co content 0≤x≤0.25 and Fe content 0≤y≤0.05 is predicted to have good magneto-controlled functional behavior.

关键词： Ni-Mn-In-Co-Fe Phase stability Magnetocaloric effect Elastocaloric effect

Neuroprotective and anti-inflammatory effects of eicosane on glutamate and NMDA-induced retinal ganglion cell injury

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 638-645页

作者： zhen-Kai Wu Huan-Yu Li You-Lin Zhu Meng-Qin Xiong jing-Xiang Zhong Department of Ophthalmology the First Affiliated Hospital of Jinan UniversityGuangzhou 510632Guangdong ProvinceChina Changde Hospital Xiangya School of MedicineCentral South University(the First People’s Hospital of Changde City)Changde 415000Hunan ProvinceChina

AIM:To investigate the protective effects,antioxidant potential,and anti-inflammatory mechanisms of eicosane on glutamate-induced cell damage and on N-methyl-Daspartate(NMDA)-induced retinal ganglion cell(RGC)injury in a mouse model of glaucoma.METHODS:The protective effects of eicosane on the rat R28 retinal precursor cell line were assessed using cell counting kit-8 assays and Hoechst-propidium iodide staining.Intracellular reactive oxygen species(ROS)production was measured using the fluorescent probe 2'-7'-dichlorofluorescin diacetate and flow cytometry.The protective role of eicosane on NMDA-induced RGC injury in a mouse glaucoma model was determined by immunostaining of frozen sections of retina.The effects of eicosane on the metabolome of the retina in mice with NMDA-induced RGC damage were evaluated by liquid chromatographymass spectroscopy(LC-MS)and untargeted metabolomics analyses.RESULTS:Eicosane treatment significantly attenuated glutamate-induced damage to R28 cells in vitro.Eicosane also protected RGCs against NMDA-induced injury in a mouse glaucoma model.Untargeted metabolomics analyses showed that eicosane increased multiple metabolites,including L-arginine and L-carnitine,in the retina.CONCLUSION:Eicosane has protective effects,antioxidant potential,and anti-inflammatory properties in an in vitro model of glutamate-induced cell damage and in an in vivo model of NMDA-induced RGC injury in mouse glaucoma through modulation of L-arginine and/or L-carnitine metabolism.

关键词： glaucoma metabolites eicosane