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Chinese Journal of Polymer Science 2024年第1期42卷 125-132,I0011页

作者： Chang-Sheng Zuo Kang Wang li-zhen sun Ting-Ting sun Department of Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310014China

The polymer translocation through a nanopore from a donor space(or named cis side) to a receiver space(trans side) in the chaperone-induced crowded environment has attracted increasing attention in recent years due to its significance in biological systems and technological applications. In this work, we mainly focus on the effects of chaperone concentration and chaperone-polymer interaction on the polymer translocation. By assuming the polymer translocation to be a quasi-equilibrium process, the free energy F of the polymer can be estimated by Rosenbluth-Rosenbluth method and then the translocation time τ can be calculated by Fokker-Plank equation based on the obtained free energy landscape. Our calculation results show that the translocation time can be controlled by independently tuning the chaperone concentration and chaperone-polymer interaction at the cis side or the trans side. There exists a critical chaperone-polymer attraction ε~*=-0.2 at which the volume exclusion and interaction effects of the chaperone can balance each other. Additionally, we also find that at large chaperone-polymer attraction, the translocation time is mainly governed by the diffusion coefficient of the polymer.

关键词： Polymer translocation Rosenbluth-Rosenbluth method Fokker-Plank equation Free energy landscapes

Translocation time of a polymer chain through an energy gradient nanopore

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Frontiers of physics 2017年第3期12卷 157-165页

作者： Meng-Bo Luo Shuang Zhang Fan Wu li-zhen sun Department of Physics Zhejiang University Hangzhou 310027 China College of Science Qinzhou University Qinzhou 535011 China Department of Applied Physics Zhejiang University of Technology Hangzhou 310023 China

The translocation time of a polymer chain through an interaction energy gradient nanopore was studied by Monte Carlo simulations and the Fokker-Planck equation with double-absorbing boundary condi- tions. Both the simulation and calculation revealed three different behaviors for polymer translocation. These behaviors can be explained qualitatively from free-energy landscapes obtained for polymer translocation at different parameters. Results show that the translocation time of a polymer chain through a nanopore can be tuned by suitably designing the interaction energy gradient.

关键词： polymer chain translocation time nanopore Monte Carlo simulation Fokker-Planck equation

1,25-dihydroxyvitamin D_3 regulates LPS-induced cytokine production and reduces mortality in rats

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World Journal of Gastroenterology 2008年第24期14卷 3897-3902页

作者： Xiao-Ping Qi Pei li Gang li zhen sun Jie-Shou li School of Medicine Nanjing University Department of GeneralSurgery Jinling Hospital 305 Zhongshandong Road Nanjing210002 Jiangsu Province China

AIM： To study the immunoregulatory effect of 1,25-dihydroxyvitamin-D3 Von dominant Thl response in rats. METHODS： Sixty adult Lewis rats were randomized into three groups. Rats in group 1 （n=25） were treated with 1,25-（OH）2D3 first and then challenged with LPS, rats in group 2 （n=25） were treated with vehicle first and then challenged with LPS. Ten animals in groups 1 and 2 were preserved for mortality observation. The remaining animals were injected （i.p） with endotoxin, 24 h after the last administration of 1,25-（OH）2D3 and vehicle. Rats in group 3 （n=10） were treated with 1,25-（OH）2D3 only. Serum IL-12, IFN-y, IL-2 and IL-4 levels were measured and target gene of 1,25-（OH）2D3 on Th cells was studied after 6 h. Gene abundance was verified by real-time quantitative PCR. RESULTS： No death occurred in rats pretreated with 1,25-（OH）2D3 after LPS injection. Death occurred 9 h after LPS injection in rats pretreated with the vehicle, and the number of deaths was 5 within 24 h, with a mortality rate of 50%. There was no change in the number of deaths within 96 h. Six hours after endotoxin stimulation, serum IL-12 and IFN-y levels decreased significantly in rats pretreated with 1,25-（OH）2D3 as compared with those in rats pretreated with the vehicle. The serum content of these two cytokines was very low in rats not challenged by endotoxin, and there was a significant difference as compared with the previous two groups. CONCLUSION： 1,25-（OH）2D3 attenuates injuryinduced by the lethal dose of 1PS, regulates Thl and Th2 cells at the transcription level, and dominantly responds to cytokine production in rats.

关键词： Endotoxin Cytokine 1,25-dihydroxy-vitamin-D3 Immunoregulation Mortality

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li zhen Ma Jin-Hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

Endoscopic management of biliary complications after orthotopic liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2006年第1期5卷 39-42页

作者： Yun-Sheng Qin, Zhao-Shen li, zhen-Xing sun, Ren-Pei Wu, Na Wang and Yin-zhen Yao Department of Hepatobiliary Surgery, First Affiliated Hospital, Zhejiang University, School of Medicine, Hangzhou 310003, China Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China Department of Hepatobiliary Surgery First Affiliated Hospital Zhejiang University School of Medicine Hangzhou China.

BACKGROUND: Biliary complications are a serious problem in patients after liver transplantation and often require reoperation. This study was conducted to summarize the endoscopic diagnosis and management of biliary complications after orthotopic liver transplantation (OLT). METHODS: From December 2000 to November 2003, twelve endoscopic retrograde cholangiopancreatographies(ERCPs) were performed in 7 patients after OLT at Digestive Endoscopic Center of Changhai Hospital in Shanghai, China. The therapeutic maneuvers included endoscopic sphincterotomy (EST), biliary stent placement, balloon and basket extraction, irrigation, and nasobiliary tube placement. A retrospective study was made to determine the types of biliary tract complications after OLT. The success of ERCP and therapeutic maneuvers was also evaluated. RESULTS: Biliary tract complications including biliary stricture, biliary leak, biliary sludge, and stump leak of the cyst duct were treated respectively by endoscopic sphincterotomy with sludge extraction, stricture dilation or endoscopic retrograde biliary drainage. Two of the 3 patients with proximal common bile duct stricture were successfully treated with ERCP and stent placement. Four patients with anastomotic stricture and/without bile leak were treated successfully by dilation and stent placement or endoscopic nosobiliary drainage. No severe ERCP-related complications occurred. CONCLUSIONS: ERCP is an effective and accurate approach for the diagnosis of biliary tract complications after OLT, and placement of a stent is a safe initial treatment for biliary complications after liver transplantation.

关键词： liver transplantation biliary tract complications endoscopic retrograde cholangiopancreatography

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： lin Peng Yu Bai Hang li Meixiu Qu zhenhua Wang Kening sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

lithium-sulfur （li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （liPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes li2S dissolution and nucleation ***,the li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： lithium sulfur batteries

Brain endothelial cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway in aging and neurodegeneration

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Neural Regeneration Research 2025年第7期20卷 2005-2007页

作者： Bryan sun Lulin li Jian Luo Palo Alto Veterans Institute for Research VA Palo Alto Health Care SystemPalo AltoCAUSA Polytrauma System of Care VA Palo Alto Health Care SystemPalo AltoCAUSA

The cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway has emerged as a key mediator of *** current studies primarily attribute its effects to neurons and glial cells,emerging research suggests that cGAS-STING signaling may play a critical role in cerebral vasculature,particularly in brain endothelial ***,studying the role 7of inflammation caused by the cGAS-STING pathway in brain endothelial cells could provide a more comprehensive understanding of neuroinflammatory disease and new avenues for therapeutic ***,we review the multifaceted role of global cGAS-STING signaling in various neurological and neuroinflammatory diseases and the potential contribution of cGAS-STING in brain endothelial cells.

关键词： stimulator interferon inflammation

Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： Wenjing Yin Hongyin Ma Yang Qu Jiaxin Ren Yingying sun zhen-Ni Guo Yi Yang Stroke Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents

Fluorinated poly(p-triphenylene isatin) anion exchange membranes based on hydrophilic hydroxyl side chain modulation for fuel cells

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Journal of Energy Chemistry 2025年第1期100卷 702-709页

作者： Yiman Gu Yanchao Zhang Zhanyu li Yijia Lei Baozeng sun Xiaoyu Yu Zhe Wang College of Chemistry and life Science Changchun University of Technology College of Chemical Engineering Changchun University of Technology School of Materials Science and Engineering Changchun University of Technology Key Laboratory of Advanced Functional Polymer Membrane Materials of Jilin Province

The development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes （AEMs） has been widely ***,the question of the“trade-off”between AEM ionic conductivity and dimensional stability remains *** strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being ***,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone （x=40,50,and 60） into the main chain of poly（p-terphenylene isatin）.Because fluorinated groups have excellent hydrophobicity,hydrophilic hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation *** results show that PTI-PTF50-NOH AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali stability under the combined effect of *** has an ionic conductivity of 133.83 mS cm-1at 80°*** addition,the OH-conductivity remains at 89%of the initial value at 80°C and 3 M KOH for 1056 h of *** cell polarization curve based on PTI-PTF50-NOH shows a power density of 734.76 mW cm-2at a current density of 1807.7 mA cm-2.

关键词： Anion exchange membranes Poly(p-terphenylene isatin) Hydrophilic-hydrophobic phase separation Fluorinated group

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie li Wenbo Yu zhenyu sun Weichen zheng liangwei Zhang Yanling Xue Wenning liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment