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Improved suboptimal Bang-Bang control of aseismic buildings with variable friction dampers

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Acta Mechanica Sinica 2007年第1期23卷 101-109页

作者： Hongnan Li Jun Li Gangbing song State Key Laboratory of Coastal and Offshore Engineering School of Civil & Hydraulic Engineering Dalian University of Technology Dalian 116023 China Anhui Modern Architecture Design & Research Institute 230041 No. 751 Rongshida Street Hefei China Department of Mechanical Engineering University of Houston Houston TX USA

One of the challenges in civil engineering is to find an innovative means of suppressing the structural vibration due to earthquake and wind loadings. This paper presents an approach for effectively suppressing vibrations of a structure with variable friction damper using a new Bang-Bang control input. A continuous function of story velocities is used to represent the improved control to reduce chatter, high frequency switching and avoid instability. With a genetic algorithm, the amplitudes of control and preloading friction forces individually prescribed in the controller and damper are optimized for enhancing the seismic performance of buildings. The control strategy for the friction damper is proposed for a three story building with one variable friction damper installed at the first story for seismic reduction. The numerical results indicate that a better reduction of peak response accelerations of floors can be achieved than those of the unmodified controller, and the adaptability of the control system is also improved greatly by comparison with the reduction ratios of the structural response energy excited by different earthquake intensities.

关键词： Suboptimal Bang-Bang controlAseismic building Variable friction damper Vibration reduction

Depuration of paralytic shellfish toxins in Japanese scallop(Patinopecten yessoensis) in natural environment

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Acta Oceanologica Sinica 2015年第12期34卷 170-174页

作者： song Tao LIU Lei song Xiaoping LIAng Yubo zhUAng Guohong Research Center of Lamprey College of Life Science Liaoning Normal University National Marine Environmental Monitoring Centers State Oceanic Administration College of Life Science and Technology Jinan University Affiliated zh.ngshan Hospital Dalian University Dalian Sanyi Animal Medicine Limited Company

To study the paralytic shellfish toxins（PSTs） depuration in Japanese scallop Patinopecten yessoensis in natural environment, Japanese scallops naturally contaminated with paralytic shellfish poisoning（PSP） toxins in the Dayao Bay in the northern Huanghai Sea are transited to Qipanmo waters in the Bohai Sea of no reported PSTs incidents. The levels and profile of PSTs during 30-day depuration are detected by the high performance liquid chromatography with fluorescence detection（HPLC-FLD）. The results show that the toxicity of the PSTs in soft tissues decreases to a relatively low level at Day 9. Moreover, the depurated ratio at the early stage of the PSTs depuration is higher than that at the later stage. The toxicity analysis of dissected organs reveals that the digestive gland is the most contaminated PSTs part, which is of important implication for the human health and scallop aquiculture. The mortality of Japanese scallops during PSTs depuration experiment is relevant to PSTs level in the soft tissue.

关键词： Paralytic shellfish toxins toxicity depuration toxin transformation Japanese scallop

Physiological normal levels of androgen inhibit proliferation of prostate cancer cells in vitro

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Asian Journal of Andrology 2014年第6期16卷 864-868页

作者： Weitao song Mohit Khera Scott Department of Urology Baylor College of Medicine Houston Texas USA.

For more than 70 years, it has been believed that a severe reduction of serum androgen levels caused regression of prostate cancer （PCa） and that increasing androgen levels enhanced growth of PCa. However, numerous recent studies have questioned this traditional belief. In our study, LNCaP and MDA PCa 2b PCa cells were treated with various levels of androgens for 10 or 20 days, and the cell growth was measured with crystal violet mitogenic assay. The results indicated that the effect of androgens on the proliferation of PCa cells occurs in a biphasic pattern, with the androgen levels promoting optimal cell growth at approximately 0.23 ng m1-1 for LNCaP cells and between I and 2 ng m1-1 for MDA PCa 2b cells. Both of the optimal androgen levels are within the adult men＇s physiological low range （〈2.4 ng ml-1）. At lower concentrations than the optimal androgen level, increasing androgen concentration promoted the proliferation of PCa cells. However, at the higher concentrations, increasing androgen concentration resulted in a dose-dependent proliferative inhibition. We conclude that physiologically normal levels of androgen inhibit the proliferation of PCa cells in vitro. However, at very low levels androgens are essential for initial growth of PCa cells.

关键词： androgen proliferation prostate cancer testosterone

高效液相色谱法同时测定环境水中多种有机污染物的研究

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化肥设计 2024年第4期62卷 10-12页

作者：毛安丽宋雅洁信阳职业技术学院河南信阳464000

旨在开发一种高效液相色谱法(HPLC)用于同时测定环境水中的多种有机污染物,以应对日益严峻的水体污染问题。针对非挥发性和热不稳定的有机污染物,优化了色谱条件,实现了苯酚、氯酚等污染物的准确测定,检出限低至2.5 ng/L。通过与气相色... 详细信息

旨在开发一种高效液相色谱法(HPLC)用于同时测定环境水中的多种有机污染物,以应对日益严峻的水体污染问题。针对非挥发性和热不稳定的有机污染物,优化了色谱条件,实现了苯酚、氯酚等污染物的准确测定,检出限低至2.5 ng/L。通过与气相色谱-质谱法(GC-MS)和超高效液相色谱-串联质谱法(UHPLC-MS/MS)的比较,HPLC显示出在操作简便性和成本效益方面的优势。结果表明,HPLC是一种有效的环境水样分析工具,适合于资源有限情况下的有机污染物监测,为水质评估和污染防治提供了科学依据。

关键词：环境水监测高效液相色谱法有机污染物分析方法比较

New types of topological superconductors under local magnetic symmetries

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National Science Review 2021年第5期8卷 85-90页

作者： Jinyu Zou Qing Xie zhida song Gang Xu Wuhan National High Magnetic Field Center & School of Physics Huazhong University of Science and Technology Department of Physics Princeton University

We classify gapped topological superconducting(TSC) phases of one-dimensional quantum wires with local magnetic symmetries, in which the time-reversal symmetry T is broken, but its combinations with certain crystalline symmetries, such as MxT, C2zT, C4zT and C6zT, are preserved. Our results demonstrate that an equivalent BDI class TSC can be realized in the MxT or C2zT superconducting wire,which is characterized by a chiral Zcinvariant. More interestingly, we also find two types of totally new TSC phases in the C4zT and C6zT superinducting wires, which are beyond the known AZ class, and are characterized by a helical Z~h invariant and Z~h ⊕Zcinvariants, respectively. In the Z~h TSC phase, Z pairs of Majorana zero modes(MZMs) are protected at each end. In the C6zT case, the MZMs can be either chiral or helical, and even helical-chiral coexisting. The minimal models preserving C4zT or C6zT symmetry are presented to illustrate their novel TSC properties and MZMs.

关键词： topological superconductor magnetic symmetry Majorana zero mode superconducting wire

Drag increment induced by a small-scale forward-facing step in Mach number5 turbulent boundary layer flows

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Chinese Journal of Aeronautics 2020年第10期33卷 2491-2498页

作者： Yifei XUE Jie REN Jinling LUO song FU School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering University of NottinghamNottingham NG72RDUnited Kingdom Beijing Aerospace Technology Institute Beijing 100074China

Small-scale roughness elements or imperfections are inevitable over the surface of a flight *** aerodynamics of these small-scale structures is difficult to predict but may play an important role in the design of a flight vehicle at high *** forward-facing step is a typical type of roughness *** experiments have been conducted to study the aerodynamics of supersonic forward-facing step,especially with a step height larger than boundary layer ***,few studies focus on small *** improve the understanding of small-scale forwardfacing step flow,we perform a series of simulations to analyze its aerodynamic influence on a Mach number 5 turbulent boundary *** general flow structures are analyzed and *** shock waves can be induced by the step even if the step height is much smaller than the boundary layer *** significant shocks are the separation shock and the reattachment *** influenced area by the step is *** the increase of the step height,the non-dimensional influence area decreases and gradually converges when the step height reaches the boundary layer *** are two normalized distributions of the skin friction coefficient and pressure coefficient associated with step *** using the normalized parameters,a power-law relationship between the step height and the drag increment coefficient is revealed and fits the simulation results *** is further illustrated that this relationship still holds when changing the inlet angle of attack,but needs slight modification with the angle of attack.

关键词： Aerodynamics Drag increment Forward-facing step Hypersonic flow Turbulent boundary layer

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血清信号素3A在类风湿关节炎的诊断价值

中国医药指南 2024年第6期22卷 5-8页

作者：宋丽云宋丽青戴薇曾频频谭立明南昌大学第二附属医院检验科江西省检验医学重点实验室南昌330008 赣州市人民医院检验科赣州341000 赣州市人民医院急诊科赣州341000

目的通过检测血清信号素3A(Sema3A)在类风湿关节炎(RA)中的表达水平,探讨其对RA的诊断价值。方法随机选取到赣州市人民医院就诊者并分为三组:(1)RA组(病情活动性RA 51例,病情非活动性RA 52例)。(2)非RA组患者93例。(3)健康对照组(HC)50... 详细信息

目的通过检测血清信号素3A(Sema3A)在类风湿关节炎(RA)中的表达水平,探讨其对RA的诊断价值。方法随机选取到赣州市人民医院就诊者并分为三组:(1)RA组(病情活动性RA 51例,病情非活动性RA 52例)。(2)非RA组患者93例。(3)健康对照组(HC)50例。采用酶联免疫吸附法(ELISA)检测血清中Sema3A、抗环瓜氨酸多肽抗体(anti-CCP)和抗RA33抗体(anti-RA33);散射比浊法检测类风湿因子(RF)和C-反应蛋白(CRP);魏氏法检测红细胞沉降率(ESR)。结果RA组血清Sema3A、anti-CCP、RF和anti-RA33表达水平分别为(27.15±8.19)ng/ml、131.31(399.50)U/ml、105.90(167.50)U/ml和30.80(23.80)U/ml,与非RA组和HC组比较,结果具有统计学差异。Sema3A对RA诊断的曲线下面积为0.76,标准误为0.03,95%可信区间(95%CI)为0.70~0.82。ROC曲线分析各项指标对RA的诊断显示,特异度最高的是anti-CCP(Sp=0.92),灵敏度最高的是RF(Se=0.83),约登指数和曲线下面积最高的是anti-CCP(YDI=0.73,AUC=0.85)。RA病情活动组和非活动组血清Sema3A水平比较具有统计学差异(P<0.01),血清Sema3A与ESR、CRP、DAS28均呈负相关(r=-0.54,r=-0.66,r=-0.42,P<0.01)。结论Sema3A对RA患者具有良好诊断价值,与非RA患者比较具有鉴别诊断价值,且可以用来判断RA疾病的严重程度。

关键词：类风湿关节炎诊断信号素3A 抗环瓜氨酸多肽抗体类风湿因子抗RA33抗体

兰州城市绿地SCCPs污染来源及人群健康风险

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中国环境科学 2024年第3期44卷 1697-1705页

作者：贾柠屹程景隆胡柏丞郭雨轩宋世杰赵渊毛潇萱兰州大学资源环境学院甘肃省环境污染预警与控制重点实验室甘肃兰州730000

观测了2022~2023年暖、冷季节兰州市主城区绿化用地土壤中短链氯化石蜡(SCCPs)的污染水平、组成特征,并利用主成分分析法、多元线性回归方法对其污染来源进行了解析,运用熵值法进行生态风险评估,并利用暴露评估模型对人群健康暴露风险... 详细信息

观测了2022~2023年暖、冷季节兰州市主城区绿化用地土壤中短链氯化石蜡(SCCPs)的污染水平、组成特征,并利用主成分分析法、多元线性回归方法对其污染来源进行了解析,运用熵值法进行生态风险评估,并利用暴露评估模型对人群健康暴露风险进行评价.结果表明研究区SCCPs浓度暖季节为19.67~938.15ng/g(平均296.00ng/g),冷季节为61.11~976.20ng/g(平均316.72ng/g),二者对应的氯含量分别为61.49%~64.62%和61.79%~64.21%.碳同系物以C10(35.80%和40.15%)、C11(24.80%和22.52%)为主,氯同系物以Cl7(30.08%和30.00%)、Cl_(8)(23.89%和24.44%)为主.来源解析显示污染可能来源于工业活动、污水处理厂废水和污泥的排放以及废水灌溉.生态风险评价表明土壤中的SCCPs不会对土壤生态造成重大危害,健康风险评价显示不论是儿童还是成人土壤SCCPs的暴露均低于每日可耐受摄入量(TDI).

关键词：短链氯化石蜡城市绿地来源解析健康风险

Telomere-dependent and telomereindependent roles of RAP1 in regulating human stem cell homeostasis

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Protein & Cell 2019年第9期10卷 649-667页

作者： Xing zh.ng Zunpeng Liu Xiaoqian Liu Si Wang Yiyuan zh.ng Xiaojuan He Shuhui Sun Shuai Ma ng Shyh-Chang Feng Liu Qiang Wang Xiaoqun Wang Lin Liu Weiqi zh.ng Moshi song Guang-Hui Liu Jing Qu State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of Sciences Beijing 100101China Advaneed Innovation Center for Human Brain Protection National Clinical Research Center for Geriatric DisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China National Laboratory of Biomacromolecules CAS Center for Excellenee in BiomacromoleculesInstitute of Biophysics Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Medicinal Chemical Biology Nankai UniversityTianjin 300071China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem cell and Regeneration Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regenerative Medicine of Ministry of Education Institute of Aging and Regenerative MedicineJinan UniversityGuangzhou 510632China Beijing Institute for Brain Disorders Capital Medical UniversityBeijing 100069China

RAP1 is a well-known telomere-binding protein, but its functions in human stem cells have remained unclea匚 Here we generated RAP1 -deficient human embryonic stem cells (hESCs) by using CRISPR/Cas9 technique and obtained RAP1-deficient human mesenchymal stem cells (hMSCs) and neural stem cells (hNSCs) via directed differentiation. In both hMSCs and hNSCs, RAP1 not only negatively regulated telomere length but also acted as a transcriptional regulator of RELN by tuning the methylation status of its gene promoter. RAP1 deficiency enhanced self-renewal and delayed senescence in hMSCs, but not in hNSCs, suggesting complicated lineage-specific effects of RAP1 in adult stem ***, these results demonstrate for the first time that RAP1 plays both telomeric and nontelomeric roles in regulating human stem cell homeostasis.

关键词： RAP1 stem cell telomere RELN methylation