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Ab initio Molecular Dynamics Study of Local Atomic Structure Evolution of U–Zr Alloy Melts upon Solidification

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金属学报:英文版 2023年第9期36卷 1549-1558页

作者： Mingfeng Liu Jiantao Wang Yongpeng Shi heyu zhu Yan Sun Peitao Liu Xing-Qiu Chen Shenyang National Laboratory for Materials Sciences Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

We study the local atomic structure evolution of UZr and UZr_(2) alloy melts upon solidification through ab initio molecular dynamics *** is achieved by analyzing in detail the temperature dependence of structure factors,pair correlation functions,the bond angle distributions,Honeycutt-Anderson index and Voronoi tessellation analysis as well as local bond orientation order *** observe that as the temperature decreases the pair correlation functions and structure factors become more structured with clear distinctions at the liquid–solid phase transition *** Honeycutt-Anderson indices and Voronoi tessellation analysis indicate that the liquid phase is predominantly comprised of the icosahedra-like local structures,whose fraction increases with decreasing temperature up to the transition temperature and then abruptly drops at the transition temperature,whereas the bcc-like local atomic structures dominate during the solidification ***,the bond orientation order analyses with\({\overline{w}}_{6}\)–\({\overline{q}}_{6}\)correlation map and bond angle distribution imply that the local structures mainly consist of the bcc-type during the solidification below the transition *** the analyses are consistent with each other,showing a first-order liquid to solid phase transition for both UZr and UZr_(2) solid solutions,which only differ in different predicted transition *** work provides a comprehensive insight into the detailed local structure evolution during the solidification of the U–Zr alloy melts at the atomic *** strategies used here can be extended to studying the liquid–solid phase transition in other alloy systems.

关键词： Local atomic structure Molecular dynamics Solidification U-Zr alloy melts

Segregation of Re at theγ/γ'boundary of Ni-based single crystal superalloys revealed by first-principles calculations based Monte-Carlo simulations

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Journal of Materials Science & Technology 2023年第12期143卷 54-61页

作者： heyu zhu Jiantao Wang Lei Wang Yongpeng Shi Mingfeng Liu Jiangxu Li Yun Chen Yingche Ma Peitao Liu Xing-Qiu Chen Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment IMR(NMSA)Shenyang 110016China

Nickel-based single crystal superalloys have been widely used in aero-engines and gas turbine *** improve the creep resistance,rhenium is often added to the ***,it is not yet fully under-stood how the added Re elements distribute in the alloys and how the microstructure evolves with the addition of ***,we performed extensive first-principles calculations based Monte-Carlo simulated annealing of Ni-Al-Re ternary alloys with different Re concentrations ranging from 0.5 at.%to 6.0 at.%.The results demonstrate that with the decreasing temperature,most of Re atoms stay in theγphase,while a few of Re atoms stay in theγ'phase and tend to occupy the Al *** low temperatures,the Re atoms segregate at theγ/γ'boundary,in good agreement with *** find that the disorder-order transition temperature of the Ni-Al-Re ternary alloys increases with the Re concentration due to the Re-enhanced Al-Al ordering *** addition,we observe that at low temperatures the Re segregation at theγ/γ'boundary promotes the formation of Ni 4 Re-or Ni 8 Re-like local structures as the Re concentration is over 2 at.%.The formation of a large amount of these local structures consumes the Re atoms in solid solutions,and thus from the solid-solution strengthening point of view,this would have a negative influence on the creep resistance of the *** work provides important atomistic insights on the Re distribution and its effects on the stability of superalloys.

关键词： creep alloys resistance

响应面法优化超声辅助提取姬菇多糖及其体外抗氧化性

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中国食品添加剂 2024年第1期35卷 143-149页

作者：陈蕾郑甜甜朱贺宇王卫东孙月娥宫号徐州市检验检测中心徐州221000 徐州工程学院食品与生物工程学院徐州221018

采用超声波辅助提取法从姬菇中提取多糖,以提取率为指标,首先通过单因素实验考察了液料比、提取温度、提取时间和超声波功率对提取率的影响,然后设计响应面试验对姬菇多糖最优提取工艺参数进行优化。结果表明,姬菇在料液比30 g/g、提取... 详细信息

采用超声波辅助提取法从姬菇中提取多糖,以提取率为指标,首先通过单因素实验考察了液料比、提取温度、提取时间和超声波功率对提取率的影响,然后设计响应面试验对姬菇多糖最优提取工艺参数进行优化。结果表明,姬菇在料液比30 g/g、提取温度75℃的条件下,采用500 W功率超声波辅助提取80 min,姬菇多糖的提取率最高可达16.38%。将提取后的姬菇粗多糖TCA脱蛋白、双氧水脱色和透析后得到纯化的精多糖,两种多糖具有一定的清除羟基自由基和ABTS+自由基能力,但是精多糖的抗氧化活性低于粗多糖,且二者的抗氧化活性均低于维生素C。因此,姬菇多糖的纯化对其抗氧化性有显著性影响,纯度越高,抗氧化性越小。

关键词：姬菇多糖响应面抗氧化

Desialylated Platelet Clearance in the Liver is a Novel Mechanism of Systemic Immunosuppression

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Research 2024年第3期2023卷 35-50页

作者： June Li Danielle Karakas Feng Xue Yingyu Chen Guangheng zhu Yeni H.Yucel Sonya A.MacParland Haibo Zhang John W.Semple John Freedman Qizhen Shi heyu Ni Department of Laboratory Medicine and Pathobiology University of TorontoTorontoONCanada Toronto Platelet Immunobiology Group TorontoONCanada Keenan Research Centre for Biomedical Science of St.Michael's Hospital TorontoONCanada Canadian Blood Services Centre for Innovation TorontoONCanada Departments of Pediatrics Medical College of WisconsinMilwaukeeWIUSA Blood Research Institute Versiti WisconsinMilwaukeeWIUSA Departments of Ophthalmology and Vision Sciences Medicine University of TorontoTorontoONCanada Faculty of Engineering and Architectural Science Ryerson UniversityTorontoONCanada Multi-Organ Transplant Program Toronto General Hospital Research InstituteTorontoONCanada Department of Immunology University of TorontoTorontoONCanada Critical Care Medicine Department ofAnesthesiology and PainUniversity of TorontoTorontoONCanada Department of Physiology University of TorontoTorontoONCanada Department of Pharmacology University of TorontoTorontoONCanada. Division of Hematology and Transfusion Medicine Lund UniversityLundSweden clinical Immunology and Transfusion Medicine Ofice of Medical ServicesRegion SkaneLundSweden Department of Medicine University of TorontoTorontoONCanada Children's Research Institute Children's WisconsinWauwatosaWIUSA Midwest Athletes Against Childhood Cancer Fund Research Center MilwaukeeWIUSA.

Platelets are small, versatile blood cells that are critical for hemostasis/thrombosis. Local platelet accumulation is a known contributor to proinflammation in various disease states. However, the anti-inflammatory/immunosuppressive potential of platelets has been poorly explored. Here, we uncovered, unexpectedly, desialylated platelets (dPLTs) down-regulated immune responses against both platelet-associated and -independent antigen challenges. Utilizing multispectral photoacoustic tomography, we tracked dPLT trafficking to gut vasculature and an exclusive Kupffer cell-mediated dPLT clearance in the liver, a process that we identified to be synergistically dependent on platelet glycoprotein Ibα and hepatic Ashwell–Morell receptor. Mechanistically, Kupffer cell clearance of dPLT potentiated a systemic immunosuppressive state with increased anti-inflammatory cytokines and circulating CD4+ regulatory T cells, abolishable by Kupffer cell depletion. Last, in a clinically relevant model of hemophilia A, presensitization with dPLT attenuated anti-factor VIII antibody production after factor VIII ( infusion. As platelet desialylation commonly occurs in daily-aged and activated platelets, these findings open new avenues toward understanding immune homeostasis and potentiate the therapeutic potential of dPLT and engineered dPLT transfusions in controlling autoimmune and alloimmune diseases.

关键词： Platelet transfusion homeostasis

二甲双胍联合胰岛素治疗妊娠期糖尿病对血糖、血清胱抑素C、血清同型半胱氨酸水平及妊娠结局的影响

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实用妇科内分泌电子杂志 2021年第36期8卷 50-53页

作者：朱和裕化州市第二人民医院妇产科广东茂名525141

目的分析二甲双胍联合胰岛素治疗妊娠期糖尿病的效果。方法选取本院收治的40例妊娠期糖尿病患者为研究对象,采用随机数字表法将其分为对照组及研究组。对照组20例采用胰岛素治疗,研究组20例在此基础上采用二甲双胍治疗,比较两组临床疗... 详细信息

目的分析二甲双胍联合胰岛素治疗妊娠期糖尿病的效果。方法选取本院收治的40例妊娠期糖尿病患者为研究对象,采用随机数字表法将其分为对照组及研究组。对照组20例采用胰岛素治疗,研究组20例在此基础上采用二甲双胍治疗,比较两组临床疗效。结果治疗前,两组血清胱抑素C(CysC)、血清同型半胱氨酸(HCY)水平比较,差异无统计学意义(P>0.05);治疗后,两组CysC、HCY水平均明显低于治疗前,且研究组各指标水平均明显低于对照组,差异有统计学意义(P0.05);治疗后,两组FPG、HbA1c、2 h PG水平均明显低于治疗前,且研究组各指标水平均明显低于对照组,差异有统计学意义(P<0.05)。研究组孕产妇并发症发生率、新生儿并发症发生率分别为5.00%、5.00%,均明显低于对照组的35.00%、40.00%,差异有统计学意义(P<0.05)。结论妊娠期糖尿病患者接受二甲双胍联合胰岛素治疗,能有效控制血糖,降低CysC和HCY水平,改善妊娠结局,具有推广价值。

关键词：二甲双胍胰岛素妊娠糖尿病血糖生化指标妊娠结局

阿仑膦酸钠和唑来膦酸预防兔激素性股骨头缺血性坏死的作用比较

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中国骨质疏松杂志 2013年第6期19卷 591-595页

作者：朱和玉朱兵孙天胜常红星吴军北京军区总医院骨科北京100700

目的通过建造兔激素性股骨头坏死模型,使用阿仑膦酸钠和唑来膦酸进行干预,观察阿仑膦酸钠和唑来膦酸能否预防兔激素性股骨头缺血性坏死,并比较两种药物的作用强弱。方法健康28周龄新西兰大白兔90只,体重(3.8±0.3)kg,雌雄不限。随机分... 详细信息

目的通过建造兔激素性股骨头坏死模型,使用阿仑膦酸钠和唑来膦酸进行干预,观察阿仑膦酸钠和唑来膦酸能否预防兔激素性股骨头缺血性坏死,并比较两种药物的作用强弱。方法健康28周龄新西兰大白兔90只,体重(3.8±0.3)kg,雌雄不限。随机分为阳性对照组(A组)、阿仑膦酸钠组(B组)、唑来膦酸组(C组),每组各30只。各组动物均经耳缘静脉注射10μg/kg大肠杆菌内毒素1次,24 h后于臀肌注射20 mg/kg甲基强的松龙,共3次,每次间隔24 h;B组同时给予阿仑膦酸钠150μg/(kg.d),共45次,颈部皮下注射;C组同时给予唑来膦酸100μg/kg,1次/4 w,共2次,耳缘静脉注射。6 w后取双侧兔股骨头骨组织,沿正中矢状面剖为两半,一半行石蜡包埋、切片,HE染色,计算空骨陷窝率,鉴定股骨头坏死情况。另一半股骨头骨组织再剖为两半,一半提取总RNA,采用实时定量聚合酶链反应(RTQ-PCR)技术检测OPG mRNA和RANKL mRNA的表达水平,并计算OPG/RANKL mRNA比值;一半提取骨蛋白,采用蛋白质免疫印迹法(Western blot)测出OPG和RANKL蛋白表达量,并计算OPG/RANKL比值。结果 A、B、C 3组动物死亡率分别为16.67%(5/30)、13.33%(4/30)、10%(3/30);空骨陷窝率(%)分别为26.33±1.17、20.85±1.47、18.55±2.43;股骨头坏死率分别为76.0%(19/25)、30.77%(8/26)、7.41%(2/27);RTQ-PCR检测股骨头骨组织OPG mRNA分别为0.85±0.086、1.22±0.085、1.62±0.097,RANKL mRNA分别为3.23±0.78、2.84±0.95、1.43±0.93;Western Blot检测股骨头骨组织OPG蛋白表达量分别为0.48±0.09、0.54±0.09、0.74±0.08;RANKL蛋白表达量分别为1.51±0.10、1.23±0.08、0.63±0.08。B、C两组股骨头坏死率低于A组,C组低于B组,差异有统计学意义(P<0.05);B组与C组比较,其OPG mRNA和蛋白表达量较低,RANKL mRNA和蛋白表达量较高,OPG/RANKL比值较低,差异有统计学意义(P<0.05)。结论唑来膦酸和阿仑膦酸钠能够有效预防兔激素性股骨头坏死的发生,其作用与对股骨头骨组织中RANKL/RANK/OPG系统的调控有关,与阿仑膦酸钠相比唑来膦酸的效果更好。

关键词：激素股骨头缺血性坏死 OPG RANKL

SARS-CoV-2 RBD and Its Variants Can Induce Platelet Activation and Clearance:Implications for Antibody Therapy and Vaccinations against COVID-19

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Research 2024年第3期2023卷 1-15页

作者： Xiaoying Ma Jady Liang Guangheng zhu Preeti Bhoria Aron A.Shoara Daniel T.MacKeigan Christopher J.Khoury Sladjana Slavkovicl Lisha Lin Danielle Karakas Ziyan Chen Viktor Prifti Zhenze Liu Chuanbin Shen Yuchong Li Cheng Zhang Jiayu Dou Zack Rousseau Jiamin Zhang Tiffany Ni Xi Lei Pingguo Chen Xiaoyu Wu Hamed Shaykhalishahi Samira Mubareka Kim AConnelly Haibo Zhang Ori Rotstein heyu Ni Department of Laboratory Medicine and Pathobiology University of TorontoTorontoONCanada Department of Laboratory Medicine Keenan Research Centre for Biomedical Science of St.Michael’s HospitalTorontoONCanada Toronto Platelet Immunobiology Group TorontoONCanada Department of Physiology University of TorontoTorontoONCanada CCOA Therapeutics Inc. TorontoONCanada Canadian Blood Services Centre for Innovation TorontoONCanada The State Key Laboratory of Respiratory Disease Guangzhou Institute of Respiratory DiseaseThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdongChina Department of Laboratory Medicine The Second Affliated Hospital of Guangzhou University of Chinese MedicineGuangzhouChina Advanced Pharmaceutics&Drug Delivery Laboratory Leslie Dan Faculty of PharmacyUniversity of TorontoTorontoONCanada Department of Medical Microbiology and Infectious Disease Sunnybrook Health Science CentreToronto ONCanada Department of Medicine University of TorontoTorontoONCanada Division of Cardiology.St.Michael's Hospital TorontoONCanada Department of Anesthesiology and Pain Medicine and Division of Critical Care Medicine University of TorontoTorontoONCanada interdepartmental Division of Critical Care Medicine University of TorontoTorontoONCanada Department of Surgery University of Toronto TorontoONCanada.

The COVID-19 pandemic caused by SARS-CoV-2 virus is an ongoing global health *** cases of COVID-19 and the rare cases of COVID-19 vaccine-induced-thrombotic-thrombocytopenia(VITT)are both associated with thrombosis and thrombocytopenia;however,the underlying mechanisms remain inadequately *** infection and vaccination utilize the spike protein receptor-binding domain(RBD)of *** found that intravenous injection of recombinant RBD caused significant platelet clearance in *** investigation revealed the RBD could bind platelets,cause platelet activation,and potentiate platelet aggregation,which was exacerbated in the Delta and Kappa *** RBD–platelet interaction was partially dependent on theβ3 integrin as binding was significantly reduced inβ3−/−***,RBD binding to human and mouse platelets was significantly reduced with relatedαIIbβ3 antagonists and mutation of the RGD(arginine-glycine-aspartate)integrin binding motif to RGE(arginine-glycine-glutamate).We developed anti-RBD polyclonal and several monoclonal antibodies(mAbs)and identified 4F2 and 4H12 for their potent dual inhibition of RBD-induced platelet activation,aggregation,and clearance in vivo,and SARS-CoV-2 infection and replication in Vero E6 *** data show that the RBD can bind platelets partially thoughαIIbβ3 and induce platelet activation and clearance,which may contribute to thrombosis and thrombocytopenia observed in COVID-19 and *** newly developed mAbs 4F2 and 4H12 have potential not only for diagnosis of SARS-CoV-2 virus antigen but also importantly for therapy against COVID-19.

关键词： Antibody diagnosis vaccine

结合态酚类物质在植物生长、食品加工及人体消化过程中的释放规律研究进展

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食品工业科技 2024年第14期45卷 408-417页

作者：王胜宇杨梅胡鹤宇朱才庆董欢欢管咏梅朱卫丰江西中医药大学药学院江西南昌330004 江西省医疗器械检测中心江西南昌330004

酚类物质具有抗氧化、抗炎、改善机体肠道健康等多种生理作用,在植物体生长及调节人体健康方面有着重要作用。相较于可直接萃取的游离态酚类物质,与多糖、蛋白质、脂质等结合的结合态酚类物质,所占比例更高,分布更广,具有潜在的应用价值... 详细信息

酚类物质具有抗氧化、抗炎、改善机体肠道健康等多种生理作用,在植物体生长及调节人体健康方面有着重要作用。相较于可直接萃取的游离态酚类物质,与多糖、蛋白质、脂质等结合的结合态酚类物质,所占比例更高,分布更广,具有潜在的应用价值,受到了越来越多的关注。结合态酚类物质从植物生长到食品加工再到人体消化利用全链条过程中,因受到多种因素影响,其组成、结构、迁移转化、赋存特征等会发生复杂的变化,研究其积累与释放规律对增强其生物活性,提高酚类利用率尤为重要。因此,本文就结合态酚类物质在植物生长、食品加工及人体消化过程中的释放研究情况进行简要综述,以期为阐明结合态酚类释放规律及提高其利用率提供理论指导。

关键词：结合态多酚释放过程植物生长食品加工人体消化

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新型电力系统惯量-频率“云-网-端”感知与控制技术展望

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高电压技术 2024年第7期50卷 3090-3104页

作者：朱介北罗贺予俞露杰徐思旸郭力源邓兆顺天津大学电气自动化与信息工程学院天津300072

在国家碳达峰、碳中和的目标下,建设新型电力系统是电力系统低碳转型的必然趋势。然而随着大规模新能源的接入,电力系统正逐步向高比例新能源和高比例电力电子设备的“双高”趋势发展,未来电力系统将面临严峻的频率稳定问题。为应对新... 详细信息

在国家碳达峰、碳中和的目标下,建设新型电力系统是电力系统低碳转型的必然趋势。然而随着大规模新能源的接入,电力系统正逐步向高比例新能源和高比例电力电子设备的“双高”趋势发展,未来电力系统将面临严峻的频率稳定问题。为应对新型电力系统惯量-频率安全运行与控制方面的挑战,围绕调频资源优化“云”、实时惯量感知预警“网”和新能源惯量补偿“端”3个维度,阐述了开展新型电力系统感知与控制研究的必要性和技术体系,论述了开展基于系统近实时频率动态预测的调频资源优化配置方法研究进展,探讨了基于同步相量测量单元的全网惯量态势感知及可视化预警技术方法,归纳了基于超级电容储存能量的新能源构网惯量模拟技术研究现状,最后对未来新型电力系统惯量-频率“云-网-端”技术的发展趋势进行了展望。

关键词：电力系统稳定电力系统控制电力系统运行频率动态优化惯量感知预警新能源惯量模拟构网控制