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Molecular Simulations in Macromolecular Science

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Chinese Journal of Polymer Science 2023年第9期41卷 1361-1370,I0005页

作者： Duo Xu hai-Xiao Wan Xue-rong Yao Juan li li-Tang Yan State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing100084China Beijing Research Institute of Chemical Industry SINOPECBeijing100013Chin

Molecular simulations are now an essential part of modern chemistry and physics,especially for the investigation of macromolecules.They have evolved into mature approaches that can be used effectively to understand the structure-to-property relationships of diverse macromolecular systems.In this article,we provide a tutorial on molecular simulations,focusing on the technical and practical aspects.Several prominent and classical simulation methods and software are introduced.The applications of molecular simulations in various directions of macromolecular science are thenfeatured by representative systems,including self-assembly,crystallization,chemical reaction,and some typical non-equilibrium systems.This tutorial paper provides a useful overview of molecular simulations in the rapid progress of macromolecular science,and suggests guidance for researchers who start exploiting molecular simulations in their study.

关键词： Molecular simulation Coarse-grained molecular dynamics Multi-scale method Polymer physics

Improving thermal stability of liNbO_(3)based electro-optical electric field sensor by depositing a TiO_(2)film

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High Voltage 2022年第5期7卷 840-846页

作者： She Wang hai Wang Chanxiao li Chijie Zhuang rong Zeng Department of Electrical Engineering Tsinghua UniversityBeijingChina Tianfu New Area Power Supply Company State Grid of Sichuan Electric Power CompanyChengduChina State Key Lab of Power Systems Tsinghua UniversityBeijingChina International Joint Laboratory on Low Carbon Clean Energy Innovation Tsinghua UniversityBeijingChina

Electro-optic electric field sensors based on liNbO3 are widely used for the measurement of electric fields or transient voltages.However,the working bias of the sensor is influenced by the temperature due to the thermo-optic effect of liNbO_(3).An athermal electrooptic electric field sensor was demonstrated by coating a thin layer of TiO_(2)film which has a negative thermo-optic coefficient,on the common-path interferometer based sensor to compensate liNbO_(3)'s positive thermo-optic coefficient.Both calculation and experimental studies were conducted.The experimental results reasonably agree well with the calculated values,and the results show the sensor coated with a 640 nm thick TiO_(2)film has a much smaller temperature dependence of 0.011°/℃compared to the initial value of 0.1°/℃.

关键词： film field stability

Uniform lipschitz Estimates of Homogenization of Elliptic Systems in Divergence Form with Dini Conditions

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 48-68页

作者： rong DONG Dong-sheng li hai-liang ZHANG School of Mathematics and Statistics Xi'an Jiaotong UniversityXi'an 710049China Departments of Mathematics Zhejiang Ocean UniversityZhoushan 316022China

The paper is devoted to the homogenization of elliptic systems in divergence form.We obtain uniform interior as well as boundary lipschitz estimates in a bounded C1,γdomain when the coefficients are Dini continuous,inhomogeneous terms are divergence of Dini continuous functions and the boundary functions have Dini continuous derivatives.The results extend Avellaneda and lin’s work[Comm.Pure Appl.Math.,40:803-847(1987)],where Holder continuity is the main assumption on smoothness of the data.

关键词： homogenization elliptic systems uniform lipschitz estimates Dini conditions

Septation of the Intrapericardial Arterial Trunks in the Ear Human Embryonic Heart

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Chinese Medical Journal 2018年第12期131卷 1457-1464页

作者： Yan-Ping Yang Hai-Rong Li Xi-Mei Cao Cong-Jin Qiao Jing Ya Department of Histology and Embryology Shanxi Medical University Taiyuan Shanxi 030001 China

Background： Outflow tract （OFT） septation defects are a common cause of congenital heart disease. Numerous studies have focused on the septation mechanism of the OFT, but have reported inconsistent conclusions. This study, therefore, aimed to investigate the septation of the aortic sac and the OFT in the early embryonic human heart. Methods： Serial sections of 27 human embryonic hearts from Carnegie stage （CS） 10 to CS19 were immunohistochemically stained with antibodies against α-smooth muscle actin （α-SMA） and myosin heavy chain. Results： At CS10-CS11, the OFT wail was an exclusively myocardial structure that was continuous with the aortic sac at the margin of the pericardial cavity. From CS13 onward, the OFT was divided into nonmyocardial and myocardial portions. The cushion formed gradually, and its distal border with the OFT myocardium was consistently maintained. The aortic sac between the fourth and sixth aortic arch arteries was degenerated. At CS16, the α-SMA-positive aortopulmonary septum formed and fused with the two OFT cushions, thus septating the nonmyocardial portion of the OFT into two arteries. At this stage, the cushions were not fused. At CS19, the bilateral cushions were fused to septate the myocardial portion of the OFT. Conclusions： Data suggest that the OFT cushion is formed before the aortopulmonary septum is formed. Thus, the OFT cushion is not derived from the aortopuhnonary septum. In addition, the nonmyocardial part of the OFT is septated into the aorta and pulmonary trunk by the aortopulmonary septum, while the main part of the cushion fuses and septates the myocardial portion of the OFT.

关键词： Aortopulmonary Septum： Human Embryonic Heart Immunohistochemistry Outflow Tract： Outflow Tract Cushion

MicroRNA and mRNA profiling of cerebral cortex in a transgenic mouse model of Alzheimer’s disease by RNA sequencing

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Neural Regeneration Research 2021年第10期16卷 2099-2108页

作者： li Zeng hai-Lun Jiang Ghulam Md Ashraf Zhuo-rong li Rui liu Organic Chemistry and Function Laboratory Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina King Fahd Medical Research Center King Abdulaziz UniversityJeddahSaudi Arabia Department of Medical Laboratory Technology Faculty of Applied Medical SciencesKing Abdulaziz UniversityJeddahSaudi Arabia

In a previous study,we found that long non-coding genes in Alzheimer’s disease(AD)are a result of endogenous gene disorders caused by the recruitment of microRNA(miRNA)and mRNA,and that miR-200a-3p and other representative miRNAs can mediate cognitive impairment and thus serve as new biomarkers for AD.In this study,we investigated the abnormal expression of miRNA and mRNA and the pathogenesis of AD at the epigenetic level.To this aim,we performed RNA sequencing and an integrative analysis of the cerebral cortex of the widely used amyloid precursor protein and presenilin-1 double transgenic mouse model of AD.Overall,129 mRNAs and 68 miRNAs were aberrantly expressed.Among these,eight down-regulated miRNAs and seven up-regulated miRNAs appeared as promising noninvasive biomarkers and therapeutic targets.The main enriched signaling pathways involved mitogen-activated kinase protein,phosphatidylinositol 3-kinase-protein kinase B,mechanistic target of rapamycin kinase,forkhead box O,and autophagy.An miRNA-mRNA network between dysregulated miRNAs and corresponding target genes connected with AD progression was also constructed.These miRNAs and mRNAs are potential biomarkers and therapeutic targets for new treatment strategies,early diagnosis,and prevention of AD.The present results provide a novel perspective on the role of miRNAs and mRNAs in AD.This study was approved by the Experimental Animal Care and Use Committee of Institute of Medicinal Biotechnology of Beijing,China(approval No.IMB-201909-D6)on September 6,2019.

关键词： 3ʹ-untranslated region Alzheimer’s disease biomarker cerebral cortex Gene Ontology high-throughput sequencing intracellular neurofibrillary tangles microtubule-associated protein-τ miRNA-mRNA network presenilin 1

A 3.06-Mb interstitial deletion on 12p11.22-12.1 caused brachydactyly type E combined with pectus carinatum

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Chinese Medical Journal 2019年第14期132卷 1681-1688页

作者： Jia Huang Hong-Yan liu rong-rong Wang hai Xiao Dong Wu Tao li Ying-hai Jiang Xue Zhang The Research Center for Medical Genomics Key Laboratory of Medical Cell BiologyChinese Ministry of EducationCollege of Basic Medical ScienceChina Medical UniversityShenyangLiaoning 110122China Institute of Medical Genetics Henan Provincial People's HospitalPeople's Hospital of Zhengzhou UniversitySchool of Clinical MedicineHenan UniversityZhengzhouHenan 450003China McKusick-Zhang Center for Genetic Medicine State Key Laboratory of Medical Molecular BiologyInstitute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing 100005China

Background:Brachydactyly,a developmental disorder,refers to shortening of hands/feet due to small or missing metacarpals/ metatarsals and/or phalanges.Isolated brachydactyly type E (BDE),characterized by shortened metacarpals and/or metatarsals,consists in a small proportion of patients with Homeobox D13 (HOXD13) or parathyroid-hormone-like hormone (PTHLH) mutations.BDE is often accompanied by other anomalies that are parts of many congenital syndromes.In this study,we investigated a Chinese family presented with BDE combined with pectus carinatum and short stature.Methods:A four-generation Chinese family was recruited in June 2016.After informed consent was obtained,venous blood was collected,and genomic DNA was extracted by standard procedures.Whole-exome sequencing was performed to screen pathogenic mutation,array comparative genomic hybridization (Array-CGH) analysis was used to analyze copy number variations,and quantitative real-time polymerase chain reaction (PCR),stride over breakpoint PCR (gap-PCR),and Sanger sequencing were performed to confirm the candidate variation.Results:A 3.06-Mb deletion (chr12:25473650-28536747) was identified and segregated with the phenotype in this family.The deletion region encompasses 23 annotated genes,one of which is PTHLH which has been reported to be causative to the BDE.PTHLH is an important regulator of endochondral bone development.The affected individuals showed bilateral,severe,and generalized brachydactyly with short stature,pectus carinatum,and prematurely fusion of epiphyses.The feature of pectus carinatum has not been described in the PTHLH-related BDE patients previously.Conclusions:The haploinsufficiency of PTHLH might be responsible for the disease in this family.This study has expanded the knowledge on the phenotypic presentation of PTHLH variation.

关键词： Brachydactyly type E Parathyroid-hormone-like hormone Pectus carinatum Short stature Copy number variation

In vitro fertilization-embryo transfer in patients with unexplained recurrent pregnancy loss

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Chinese Medical Journal 2021年第20期134卷 2421-2429页

作者： Tai-Yang li rong li lin Zeng li li Jie Qiao Ping liu hai-Yan Wang Center of Reproductive Medicine Peking University Third HospitalBeijing 100191China Clinical Epidemiology Research Center Peking University Third HospitalBeijing 100191China

Background:Empiric therapy for patients with unexplained recurrent pregnancy loss(URPL)is not precise.Some patients will ask for assisted reproductive technology due to secondary infertility or advanced maternal age.The clinical outcomes of URPL patients who have undergonein vitro fertilization-embryo transfer(IVF-ET)require elucidation.The IVF outcome and influencing factors of URPL patients need further study.Methods:A retrospective cohort study was designed,and 312 infertile patients with URPL who had been treated during January 2012 to December 2015 in the Reproduction Center of Peking University Third Hospital were included.By comparing clinical outcomes between these patients and those with tubal factor infertility(TFI),the factors affecting the clinical outcomes of URPL patients were analyzed.Results:The clinical pregnancy rate(35.18%vs.34.52%in fresh ET cycles,P=0.877;34.48%vs.40.27%in frozen-thawed ET cycles,P=0.283)and live birth rate(LBR)in fresh ET cycles(27.67%vs.26.59%,P=0.785)were not significantly different between URPL group and TFI group.URPL group had lower LBR in frozen-thawed ET cycles than that of TFI group(23.56%vs.33.56%,P=0.047),but the cumulative LBRs(34.69%vs.38.26%,P=0.368)were not significantly different between the two groups.The increased endometrial thickness(EMT)on the human chorionic gonadotropin day(odds ratio[OR]:0.848,95%confidence interval[CI]:0.748-0.962,P=0.010)and the increased number of eggs retrieved(OR:0.928,95%CI:0.887-0.970,P=0.001)were protective factors for clinical pregnancy in stimulated cycles.The increased number of eggs retrieved(OR:0.875,95%CI:0.846-0.906,Plive birth outcome.Conclusion:After matching ages,no significant differences in clinical outcomes were found between the patients with URPL and the patients with TFI.A thicker endometrium and more retrieved oocytes increase the

关键词： Unexplained recurrent pregnancy loss Cumulative live birth rate Tubal factor infertility

Application of neutron scattering in organic photovoltaic materials

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Chinese Journal of Structural Chemistry 2023年第5期42卷 34-43页

作者： li-Ming Wang Lei Cao Wen-hai Ji rong Du Ming Tang Sheng-Lan Chen li-li Yan Yinguo Xiao Jun-rong Zhang Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Spallation Neutron Source Science Center(SNSSC) Dongguan 523803China School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen518055China

Over last decades,the development of new organic materials has contributed to the rapid increase of high-power conversion efficiency of photovoltaic cells.At this stage,to understand the structure and the dynamic of materials is of significant importance for designing novel low-cost photovoltaic cells with superior performance.Neutron scattering is a powerful tool to provide unique and non-destructive information for the organic photovoltaic materials with particular advantages of addressing different parts of organic system by deuterium or tritium substitution.In addition,by employing several neutron scattering methods together,it is possible to further access the static structure and dynamic relaxation of the materials.With this perspective review,we introduce three neutron scattering techniques,including neutron reflectivity,small angle neutron scattering,grazing incidence small angle neutron scattering and quasi-elastic neutron scattering,and their applications on the organic photovoltaic materials.

关键词： Neutron scattering techniques Organic photovoltaic materials Static morphology Dynamic structures

Bis(2-butoxyethyl) Phthalate Delays Puberty Onset by Increasing Oxidative Stress and Apoptosis in Leydig Cells in Rats

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Biomedical and Environmental Sciences 2023年第1期36卷 60-75页

作者： liU Miao Qing CHEN hai Qiong DAI hai Peng li Jing Jing TIAN Fu Hong WANG Yi Yan CHEN Cong De li Xiao Heng li Jun Wei li Zhong rong GE Ren Shan Department of Pediatric Surgery the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical UniversityWenzhou 325027ZhejiangChina Key Laboratory of Structural Malformations in Children of Zhejiang Province Wenzhou 325000ZhejiangChina

Objective This study investigated the effects of bis(2-butoxyethyl) phthalate(BBOP) on the onset of male puberty by affecting Leydig cell development in rats.Methods Thirty 35-day-old male Sprague-Dawley rats were randomly allocated to five groups mg/kg bw per day that were gavaged for 21 days with BBOP at 0, 10, 100, 250, or 500 mg/kg bw per day. The hormone profiles;Leydig cell morphological metrics;mRNA and protein levels;oxidative stress;and AKT,mTOR, ERK1/2, and GSK3β pathways were assessed.Results BBOP at 250 and/or 500 mg/kg bw per day decreased serum testosterone, luteinizing hormone, and follicle-stimulating hormone levels mg/kg bw per day(P < 0.05). BBOP at 500 mg/kg bw per day decreased Leydig cell number mg/kg bw per day and downregulated Cyp11a1, Insl3, Hsd11b1,and Dhh in the testes, and Lhb and Fshb mRNAs in the pituitary gland(P < 0.05). The malondialdehyde content in the testis significantly increased, while Sod1 and Sod2 mRNAs were markedly downregulated, by BBOP treatment at 250–500 mg/kg bw per day(P < 0.05). Furthermore, BBOP at 500mg/kg bw per day decreased AKT1/AKT2, mTOR, and ERK1/2 phosphorylation, and GSK3β and SIRT1levels mg/kg bw per day(P < 0.05). Finally, BBOP at 100 or 500 μmol/L induced ROS and apoptosis in Leydig cells after 24 h of treatment in vitro(P < 0.05).Conclusion BBOP delays puberty onset by increasing oxidative stress and apoptosis in Leydig cells in rats.The graphical abstract is available on the website ***.

关键词： Bis(2-butoxyethyl)phthalate Leydig cells Testosterone Oxidative stress Gonadotropin