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Isogeometric Analysis of Hyperelastic Material Characteristics for Calcified Aortic Valve

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2773-2806页

作者： Long chen ting Li Liang Liu Wenshuo Wang Xiaoxiao Du Wei Wang School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai200093China Department of Cardiac Surgery Zhongshan HospitalFudan UniversityShanghai200093China School of Mechanical Engineering and Automation Beihang UniversityBeijing100191China

This study explores the implementation of computed tomography(CT)reconstruction and simulation techniques for patient-specific valves,aiming to dissect the mechanical attributes of calcified valves within transcatheter heart valve replacement(TAVR)*** order to facilitate this exploration,it derives pertinent formulas for 3D multi-material isogeometric hyperelastic analysis based on Hounsfield unit(HU)values,thereby unlocking foundational capabilities for isogeometric analysis in calcified aortic valves.A series of uniaxial and biaxial tensile tests is executed to obtain an accurate constitutive model for calcified active *** mitigate discretization errors,methodologies for reconstructing volumetric parametric models,integrating both geometric and material attributes,are *** these analytical formulas,constitutive models,and precise analytical models to isogeometric analyses of calcified valves,the research ascertains their close alignment with experimental results through the close fit in displacement-stress curves,compellingly validating the accuracy and reliability of the *** study presents a step-by-step approach to analyzing themechanical characteristics of patient-specific valves obtained fromCT images,holding significant clinical implications and assisting in the selection of treatment strategies and surgical intervention approaches in TAVR procedures.

关键词： Calcified aortic valves tensile test constitutive relations CT reconstruction isogeometric hyperelastic analysis

Theoretical insights into thermal transport and structural stability mechanisms of triaxial compressed methane hydrate

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Chinese Physics B 2024年第9期33卷 494-504页

作者： Dong-Sheng chen ting-ting Miao cheng Chang Xu-Yang Guo Meng-Yan Guan and Zhong-Li Ji Beijing Key Laboratory of Process Fluid Filtration and Separation College of Mechanical andTransportation EngineeringChina University of Petroleum-BeijingBeijing 102249China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum-BeijingBeijing 102249China

The heat transfer and stability of methane hydrate in reservoirs have a direct impact on the drilling and production efficiency of hydrate resources,especially in complex stress environments caused by formation *** this study,we investigated the thermal transport and structural stability of methane hydrate under triaxial compression using molecular dynamics *** results suggest that the thermal conductivity of methane hydrate increases with increasing compression *** phonon transport mechanisms were identified as factors enhancing thermal *** low compressive strains,a low-frequency phonon transport channel was established due to the overlap of phonon vibration peaks between methane and water *** high compressive strains,the filling of larger phonon bandgaps facilitated the opening of more phonon transport ***,we found that a strain of􀀀0.04 is a watershed point,where methane hydrate transitions from stable to ***,a strain of􀀀0.06 marks the threshold at which the diffusion capacities of methane and water molecules are at their *** a higher strain of􀀀0.08,the increased volume compression reduces the available space,limiting the diffusion ability of water and methane molecules within the *** synergistic effect of the strong diffusion ability and high probability of collision between atoms increases the thermal conductivity of hydrates during the unstable period compared to the stable *** findings offer valuable theoretical insights into the thermal conductivity and stability of methane hydrates in reservoir stress environments.

关键词： methane hydrate molecular dynamics thermal transport triaxial compression structural stability

Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1317-1335页

作者： Chein-Shan Liu Jian-Hung Shen Chung-Lun kuo Yung-Wei chen Center of Excellence for Ocean Engineering Taiwan Ocean UniversityKeelung202301TaiwanChina Department of Marine Engineering Taiwan Ocean UniversityKeelung202301TaiwanChina

This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue *** each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex ***,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation *** real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very *** the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency.

关键词： Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method

OSDA-free synthesis of FeZSM-22 zeolite from natural minerals for n-octane hydroisomerization

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Chinese Journal of Chemical Engineering 2024年第2期66卷 51-59页

作者： Tiesen Li ting chen Yinghui Ye Peng Dong tinghaiWang Qingyan Cui Chan Wang Yuanyuan Yue National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350002China Qingyuan Innovation Laboratory Quanzhou 362801China

A seed-directed approach to synthesizing Fe ZSM-22 zeolite without organic structure directing agent(OSDA)was developed by using Fe-rich diatomite as all aluminum and iron *** Fe ZSM-22zeolite with optimal crystallinity and purity can be obtained by systematically adjusting feed composition and synthesis *** show that Fe ZSM-22 zeolite synthesized with OSDA-free owns high crystallinity,obvious thin needle-shaped morphology and high Bronsted/Lewis acid ***,when used for n-octane hydroisomerization reaction,its derived catalyst exhibits the best catalytic performance reflected by the highest selectivity to C_(8)isomers compared to the two reference catalysts prepared based on a Fe-containing and a Fe-free ZSM-22 synthesized through an OSDA-directed route from natural diatomite and conventional chemicals,*** work provides an alternative route to sustainably synthesizing heteroatomic zeolites with high performance.

关键词： FeZSM-22 zeolite OSDA-free synthesis Natural minerals n-octane hydroisomerization

Application of nanoscale metal–organic frameworks in tumor immunotherapy

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Rare Metals 2024年第10期43卷 4867-4883页

作者： Xiao-Xuan Zeng Jing-Sheng Lu Dong-Wei Ma Yu-ting Huang Ling chen Gang Wang Qing chen Ning Lin College of Pharmacy Guangxi Scientific Research Center of Traditional Chinese MedicineGuangxi University of Chinese Medicine Guangxi Zhuang Yao Medicine Center of Engineering and Technology

Immunotherapy has attracted wide attention because it can not only kill tumor cells but also effectively prevent tumor recurrence. However, due to the poor efficacy of the monotherapy in tumor immunotherapy, combination therapies are needed to enhance their efficacy,such as chemodynamic therapy/immunotherapy, photodynamic therapy/immunotherapy, sonodynamic therapy/immunotherapy and so on. Nanoscale metal–organic frameworks(nMOFs) are widely used for drug delivery because of their rich and variable composition, high drug loading capacity and good biodegradability. Compared with other conventional drug delivery systems(DDSs),nMOFs play more advantageous role in inducing immune cell death of tumor cells and combination therapies. This article focuses on the application of n MOFs in tumor immunotherapy in terms of their use as gatekeepers, supplementary agents and drug carriers, respectively, with the aim of providing some ideas and references for the design of smart nanoscale DDS for tumor immunotherapy.

关键词： Drug delivery system Immunotherapy Metal–organic frameworks Tumor

Identification of two compound heterozygous GNRHR mutations in two siblings with congenital hypogonadotropic hypogonadism

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Asian Journal of Andrology 2024年第1期26卷 120-122页

作者： Xiao-Bin Wang Ping chen Xue-Er Yu Zu-Liang Yao ting-Chao Guo Bo-chen Pan Center for Reproductive Medicine Department of Obstetrics and GynecologyShengjing Hospital of China Medical UniversityShenyang 110004China NuProbe Shanghai 200433China Urology Surgery of The Affiliated Reproductive Hospital of China Medical University and Liaoning Key Laboratory of Reproductive Health Liaoning Research Institute of Family Planning(The Affiliated Reproductive Hospital of China Medical University)Shenyang 110031China NHC Key Laboratory of Reproductive Health and Medical Genetics China Medical UniversityShenyang 110122China

DearEditor,Congenital hypogonadotropic hypogonadism(CHH)is a rare genetic disease characterized by gonadotropin-releasing hormone(GnRH)deficiency or insufficiency and normal hypothalamic-pituitary structures,resulting in defective sexual maturation or/and infertility.!CHH presents as a variety of nonreproductive phenotypes,such as renal hypoplasia,dental hypoplasia,or oculomotor abnormalities.

关键词： pogon compound ism

Vitamin A deficiency suppresses CEACAM1 to impair colonic epithelial barrier function via downregulating microbial-derived short-chain fatty acids

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Genes & Diseases 2024年第2期11卷 1066-1081页

作者： Junyan Yan Lu Xiao Di Feng Baolin chen ting Yang Bei Tong Ruifang Luo Yuting Wang Jie chen Children Nutrition Research Center Children's Hospital of Chongqing Medical UniversityChongqing Key Laboratory of Child Nutrition and HealthMinistry of Education Key Laboratory of Child Development and DisordersNational Clinical Research Center for Child Health and DisordersChongqing 401122China Department of Gastroenterology Children's Hospital of Chongqing Medical UniversityChongqing 401122China

Vitamin A (VA) plays an essential role in modulating both the gut microbiota and gut barrier ***-chain fatty acids (SCFAs),as metabolites of the gut microbiota,protect the physiological intestinal barrier;however,they are compromised when VA is ***,there is an urgent need to understand how and which SCFAs modulate colonic epithelial barrier integrity in VA deficiency (VAD).Herein,compared with normal VA rats (VAN),at the beginning of pregnancy,we confirmed that the colonic desmosome junction was impaired in the VAD group,and the amounts of acetate,propionate,and butyrate declined because of the decreased abundance of SCFA-producing bacteria (Romboutsia ,Collinsella ,and Allobaculum ).The differentially expressed genes correlated with the gut barrier and the histone deacetylase complex between the VAD and VAN groups were enriched by RNA *** the VAD group,the expression levels of colonic CEA cell adhesion molecule 1 (CEACAM1) were down-regulated,and the levels of histone deacetylase 1 (HDAC1) and HDAC3 were ***,the above changes in the VAD groups were rescued by VA supplementation in the early postnatal *** study indicated that in Caco-2 cells,butyrate treatment significantly repressed the enrichment of HDAC3 on the promoter of the CEACAM1 gene to induce its *** findings support that butyrate intervention can alleviate the impairment of colonic barrier function caused by VAD,and timely postnatal VA intervention may reverse the damage caused by VAD on gut barrier integrity during pregnancy.

关键词： CEACAM1 Colonic epithelial barrier HDAC3 Short-chain fatty acids Vitamin A deficiency

Bacterial microcompartment-mimicking Pickering emulsion droplets for detoxification of chemical threats under sweet conditions

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Science China Chemistry 2024年第9期67卷 3039-3049页

作者： Xiao Xu Wenqi Xie ting Wu chen chen Xiaoning chen Yuheng Yang Hao Lian Hao chen Xiaofeng cheng Zhitong chen Guojun chen Chaoqun Liu Lanlan chen Yu He Zhaowei chen Bernard P.Binks Huanghao Yang New Cornerstone Science Laboratory MOE Key Laboratory for Analytical Science of Food Safety and BiologyCollege of ChemistryFuzhou UniversityFuzhou 350002China Institute of Biomedical and Health Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Department of Biomedical Engineering and the Rosalind&Morris Goodman Cancer Research Institute McGill UniversityMontreal QC H3A 1A3Canada School of Pharmacy Henan UniversityKaifeng 475004China Department of Chemistry University of HullHull HU67RXUK

Chemical warfare agents represent a severe threat to mankind and their efficient decontamination is a global ***,traditional disposal strategies have limitations,including high energy consumption,use of aggressive reagents and generation of toxic ***,inspired by the compartmentalized architecture and detoxification mechanism of bacterial microcompartments,we constructed oil-in-water Pickering emulsion droplets stabilized by hydrogen-bonded organic framework immobilized cascade enzymes for decontaminating mustard gas simulant(2-chloroethyl ethyl sulfide,CEES)under sweet *** exemplified droplet systems were developed with two-enzyme(glucose oxidase/chloroperoxidase)and threeenzyme(invertase/glucose oxidase/chloroperoxidase)cascades,both achieving over 6-fold enhancement in decontamination efficiency compared with free enzymes and>99% selectivity towards non-toxic *** found that the favored mass transfer of sugars and CEES from their respective phases to approach the cascade enzymes located at the droplet surface and the facilitated substrate channeling between proximally immobilized enzymes were key factors in augmenting the decontamination *** importantly,the robustness of immobilized enzymes enabled easy reproduction of both the droplet formation and detoxification performance over 10 cycles,following long-term storage and in far-field locations.

关键词： Pickering emulsion biomimetics chemical warfare agent bacterial microcompartment biocatalysis

A fungal CYP from Beauveria bassiana with promiscuous steroid hydroxylation capabilities

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Chinese Chemical Letters 2024年第5期35卷 218-222页

作者： Yu Peng Yue Wang Tian-Jiao chen Jing-Jing chen Jin-Ling Yang ting Gong Ping Zhu State Key Laboratory of Bioactive Substance and Function of Natural Medicines NHC Key Laboratory of Biosynthesis of Natural ProductsCAMS Key Laboratory of Enzyme and Biocatalysis of Natural DrugsInstitute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Hydroxylation of steroid core is critical to the synthesis of steroid *** sp^(3) C-H hydroxylation is challenging through chemical catalysis,alternatively,fungal biotransformation offers a possible solution to this ***,mining and metabolic engineering of cytochrome P450 monooxygenases(CYPs)is usually regarded as a more eco-friendly and efficient ***,we report the mining and identification of a new steroid CYP(CYP68BE1)from Beauveria bassiana by transcriptomics,heterologous expression,in vivo and in vitro functional *** catalytic promiscuity of CYP68BE1 was explored,and CYP68BE1 showed promiscuously and catalytically versatile,which is qualified for monohydroxylation on C11α,C1α,C6βand dihydroxylation on C1β,11αand C6β,11αof six steroids,leading to the production of key steroid intermediates required in the industrial synthesis of some indispensable steroid *** dynamics simulations were performed,revealing the molecular basis of different binding orientations of CYP68BE1 with different *** discovery of CYP68BE1 offers a promising biocatalyst for enriching the steroid structural and functional diversity,which also can be applied to biosynthesize valuable steroid drug intermediates.

关键词： Fungal CYPs Steroid hydroxylase Beauveria bassiana Promiscuous biocatalyst Molecular dynamics