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Regularity of Invariant Sets in Variable Internal Damped Wave Equations

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 952-974页

作者： Gao-cheng yuE yu-xin liang Jia-jia YANG Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106China

In this paper we prove that every compact invariant subset■associated with the semigroup{Sn,k(t)}t≥0 generated by wave equations with variable damping,either in the interior or on the boundary of the domainΩwhereΩ■R^3 is a smooth bounded domain,in H^10(Ω)×L^2(Ω)is in fact bounded in D(B0)×H^10(Ω)As an application of our results,we obtain the upper-semicontinuity for global attractor of the weakly damped semilinear wave equation in the norm of H^1(Ω)×L^2(Ω)when the interior variable damping converges to theboundary damping in the sense of distributions.

关键词： Damped wave equation boundary damping invariant set regularity

Quantitative Structure-activity Relationship Models of Monomer Reactivity

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Chinese Journal of Structural Chemistry 2019年第11期38卷 1867-1873页

作者： yu xin-liang YI Xiang YANG Hui-Qiong Hunan Provincial Key Laboratory of Environmental Catalysis & Waste Regeneration College of Chemistry and Chemical Engineering Hunan Institute of Engineering

The reactivity parameters,Q and e,in the Q-e scheme reflect the reactivities of a monomer(or a radical)in free-radical *** applying multiple linear regression(MLR)analysis,the optimal quantitative structure-activity relationship(QSAR)model for the reactivity parameter lnQ was developed based on five descriptors(NAF,NOF,EαLUMO,EβHOMO,and EβLUMO)and 69 monomers with the root mean square(rms)error of *** optimal MLR model of the parameter e obtained from five descriptors(TOcl,NpN,NSO,EαHOMO and DH)and 68 monomers produced rms error of *** with previous models,the two optimal MLR models in this paper show satisfactory statistical *** feasibility of combining 2D descriptors obtained from the monomers and 3D descriptors calculated from the radical structures(formed from monomers+H )to predict parameters Q and e has been demonstrated.

关键词： density functional theory molecular descriptors multiple linear regression quantum chemical descriptors quantitative structure-activity relationship

Evolution of High-energy Electron Distribution in Pulsar Wind Nebulae

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Research in Astronomy and Astrophysics 2024年第7期24卷 198-214页

作者： Yi-Ming Liu Hou-Dun Zeng yu-liang xin Si-Ming Liu Yi Zhang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China

In this paper,we analyze the spectral energy distributions of 17 powerful(with a spin-down luminosity greater than10~(35)erg s~(-1))young(with an age less than 15,000 yr)pulsar wind nebulae(PWNe)using a simple timein-dependent one-zone emission *** aim is to investigate correlations between model parameters and the ages of the corresponding PWNe,thereby revealing the evolution of high-energy electron distributions within *** findings are as follows:(1)The electron distributions in PWNe can be characterized by a double power-law with a super-exponential cutoff.(2)As PWNe evolve,the high-energy end of the electron distribution spectrum becomes harder with the index decreasing from approximately 3.5 to 2.5,while the low-energy end spectrum index remains constant near 1.5.(3)There is no apparent correlation between the break energy or cutoff energy and the age of PWNe.(4)The average magnetic field within PWNe decreases with age,leading to a positive correlation between the energy loss timescale of electrons at the break energy or the high-energy cutoff and the age of the PWN.(5)The total electron energy within PWNe remains constant near 2×10~(48)erg,while the total magnetic energy decreases with age.

关键词： radiation mechanisms non-thermal-ISM general-ISM supernova remnants-gamma-rays general

A Novel Grid Synchronization Control of Doubly-fed Induction Generator

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电力电子技术 2012年第4期46卷 38-42页

作者： ZHAN liang-yu JIN xin-min ZHANG Lu Institute of Renewable Energy Beijing Jiaotong University Beijing 100044 China

The dynamic performance of doubly-fed induction generator(DFIG) before and after connection is analyzed based on corresponding mathematical models and transfer functions in decoupled vector *** parameter tuning methods of rotor current regulator before and after connection are *** reach same dynamic performance the parameters should take different values and be switched before and after *** on one hand the closing moment of stator contactor is difficult to get as the feedback signal is usually twenty millisecond delay or *** delay in parameter switching will affect rotor current and torque dynamics during the delayed period after connection. On the other hand parameter switching is *** a synchronization control strategy without parameter switching is proposed and analyzed in detail,which has linear rising exciting current to avoid current overshooting. The dynamic performance of the proposed strategy is analyzed in frequency domain and implemented on a DFIG experimental platform *** proposed synchronization strategy is validated by experimental results.

关键词：摘要编辑部编辑工作读者

CT引导下经胸穿刺活检术中胸膜局部麻醉控制疼痛的有效性和安全性研究

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中国CT和MRI杂志 2025年第1期23卷 97-99页

作者：余良鑫陈伟强郭春明丁勇汕头市中心医院麻醉科广东汕头515000 广东药科大学附属第一医院麻醉科广东广州510699

目的 CT引导下经胸穿刺活检术(TNB)中胸膜局部麻醉控制疼痛的有效性和安全性研究。方法回顾性分析本院于2023年1月至2023年12月在CT引导下接受(A)胸膜和皮肤麻醉(胸膜麻醉组)或(B)单纯皮肤麻醉(皮肤麻醉组)的行TN B患者。疼痛评分在0-... 详细信息

目的 CT引导下经胸穿刺活检术(TNB)中胸膜局部麻醉控制疼痛的有效性和安全性研究。方法回顾性分析本院于2023年1月至2023年12月在CT引导下接受(A)胸膜和皮肤麻醉(胸膜麻醉组)或(B)单纯皮肤麻醉(皮肤麻醉组)的行TN B患者。疼痛评分在0-5的数字等级范围内报告,疼痛评分3-5被归类为显著疼痛。使用多变量线性回归模型和Logistic回归模型评估胸膜麻醉与疼痛评分、显著疼痛和气胸的关系。结果 111例患者胸麻组疼痛评分(1.40±1.0 vs.2.3±1.1,P<0.001)低于皮麻组(18.4%[7/38]vs.42.5%[31/73],P=0.020)。疼痛评分与胸膜麻醉呈负相关(P<0.001),与手术时间呈正相关(P<0.001)。显著疼痛与胸膜麻醉呈负相关(P=0.004),与手术时间呈正相关(P<0.001)。胸膜麻醉与气胸或胸管置入无关(P=0.806和0.291)。结论胸膜麻醉在不增加气胸风险的前提下,减轻了患者的主观疼痛。

关键词： CT 经胸穿刺活检术胸膜局部麻醉控制疼痛

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自由基共聚合中单体Q-e活性参数预测

化学学报 2010年第22期68卷 2264-2272页

作者：禹新良湖南工程学院化学化工学院湘潭411104 湘潭大学化学学院环境友好化学与应用教育部重点实验室湘潭411105

Q-e方程在解释自由基共聚合中单体的活性时相当有效.为得到可靠的Q,e活性参数结构-性能定量关系(QSPR)模型,采用密度泛函理论(DFT)UB3LYP方法在6-31G(d)基组水平上对60种结构为CH3C1H2—C2HR3·自由基(C1H2=C2HR3+CH3·→CH3C1H2—C2HR3... 详细信息

Q-e方程在解释自由基共聚合中单体的活性时相当有效.为得到可靠的Q,e活性参数结构-性能定量关系(QSPR)模型,采用密度泛函理论(DFT)UB3LYP方法在6-31G(d)基组水平上对60种结构为CH3C1H2—C2HR3·自由基(C1H2=C2HR3+CH3·→CH3C1H2—C2HR3·)进行了计算.两组包含原子电荷及前线分子轨道能级的量子化学参数分别用来建立Q,e活性参数的人工神经网络(ANN)模型.通过试差法调整网络参数得到最佳ANN模型,两者均为3-5-1结构.参数Q,e预测值与实验值接近,测试集相关系数分别为0.990(rms=0.269)和0.943(rms=0.331).而且Q,e模型的外部验证系数qe2xt分别为0.980和0.873,这结果显示两模型具有好的推广预测能力.因此本工作介绍的ANN模型是精确而可靠的;从自由基CH3C1H2—C2HR3·结构获得参数预测Q及e值是可行的.

关键词：人工神经网络自由基共聚合 Q-e方程结构-性能定量关系量子化学参数自由基

Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen Zuo-Tang liang yu-Gang Ma xin-Li Sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

Complications and clinical outcomes of minimally invasive transforaminal lumbar interbody fusion for the treatment of one- or two.-level degenerative disc diseases of the lumbar spine in patients older than 65 years

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Chinese Medical Journal 2012年第14期125卷 2505-2510页

作者： WU Wen-jian liang yu ZHANG xin-kai CAO Peng ZHENG Tao Department of Orthopaedic Surgery Shanghai Ruijin HospitalShanghai Jiao Tong University School of Medicine ShanghaiInstitute of Orthopaedics and Traumatology Shanghai 200025China

Background Minimally invasive transforaminal lumbar interbody fusion （MIS-TLIF） has been successfully used to treat degenerative diseases of the lumbar spine. There are few reports comparing the complications and clinical outcomes in older patients who have undergone one- or two-level MIS-TLIF with those of younger patients. The aim of this study was to investigate the clinical outcomes of MIS-TLIF in the treatment of degenerative disc disease of lumbar spine of the patients older than 65 years, with an emphasis on perioperative complications compared to the younger patients. Methods One hundred and fifty-one consecutive cases of one- or two-level degenerative disc disease of lumbar spine treated with MIS-TLIF were reviewed for the radiological and clinical outcomes. They were divided into elderly group （age 〉65 years old） and younger group （age 〈65 years old）, and were followed for at least 6 months. Radiographs were obtained before and after surgery, 3 months postoperatively, and at the final follow-up to determine the presence of fusion, hardware-related problems. The clinical outcomes were evaluated using the Oswestry Disability Index （ODI） before and after surgery, and at the final follow-up. The visual analogue scale （VAS） score of back and leg pain were evaluated as well. The intra-operative data and peri-operative complications were recorded. Results The mean age of these patients at operation was （57.7±14.2） years （range 26-82 years）. Of 151 patients, 62 were 65 years or older. The elderly patients had more comorbidities and more porportion of lumbar canal stenosis. The overall fusion rate was 88.4% at the final follow-up, with no significant difference between younger and elderly patients. The ODI, the VAS of back pain and radicular pain of both young and elderly group were significantly improved after surgery and at the final follow-up, without significant difference between two groups. There were 16 complications with an incidence of 10.6%, including 7 m

关键词： minimally imvasive spine surgery, transforaminal lumbar interbodyfusion elderly

Killing effect of TNF-related apoptosis inducing ligand regulated by tetracycline on gastric cancer cell line NCI-N87

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World Journal of Gastroenterology 2001年第4期7卷 559-562页

作者： Xiao-Chao Wei xin-Juan Wang Kai-Chen Lei Zhang yu liang xin-Li Lin Department of Biochemistry and Molecular Biology,Peking University Health Science Center,Beijing 100083,ChinaProtein Studies,Oklahoma Medical Research Foundation,Oklahoma City,OK 73104,USA Department of Biochemistry and Molecular Biology Peking University Health Science Center 38 Xue Yuan Road Haidian District Beijing 100083 China. xinjuan@***

AIM: To clone the cDNA fragment of human TRAIL (TNF-related apoptosis inducing ligand) into a tetracycline-regulated gene expression system, the RevTet-On system, transduce expression vectors into a gastric carcinoma cell line-NCI-N87 and examine the effects of controlled expression of TRAIL in vitro on the gastric carcinoma cells. METHODS: The full-length cDNA of TRAIL was inserted into a vector under the control of the tetracycline-responsive element (TRE) to obtain the plasmid pRevTRE-TRAIL, which was transfected into a packaging cell line PT67. In addition, vector pRev-Tet On and pRevTRE were also transfected into PT67 separately. After hygromycin and G418 selection, the viral titer was determined. The medium containing retroviral vectors was collected and used to transduce a gastric carcinoma cell line NCI-N87. The resulting cell line NCI-N87-Tet On TRE-TRAIL and a control cell line, NCI-N87 Tet On-TRE, were established. TRAIL expression in the cell line was induced by incubating cells with doxycycline (Dox), which is a tetracycline analogue. The killing effect on gastric carcinoma cells was analyzed after induction. RESULTS: The recombinant plasmid pRev-TRE-TRAIL was constructed. After hygromycin or G418 selection, the producer cell lines PT67-TRE, PT67-TRE-TRAIL and PT67-Tet On were obtained,with titers of about 10(8)CFU.L(-1). By transducing NCI-N87 cells with retroviral vectors from these cell lines, stable cell lines NCI-N87-Tet-On TRE-TRAIL (NN3T) and control cell line NCI-N87-Tet-On-TRE (NN2T) were established. The growth curves of the selected cell lines were the same with the wild type NCI-N87. When Dox was added, cell death was obvious in the test groups (29%-77%), whereas no difference was observed in control and wild type cell lines. With the addition of a medium from the test group, human leukemia cell line Jurkat was activated till death (83%), indicating the secretion of active TRAIL proteins from the test cells to the medium. CONCLUSION: With th

关键词： Stomach Neoplasms 3T3 Cells Animals Anti-Bacterial Agents Apoptosis Apoptosis Regulatory Proteins Doxycycline Gene Expression Regulation, Neoplastic Genetic Vectors Humans Jurkat Cells Membrane Glycoproteins Mice Research Support, Non-U.S. Gov't Retroviridae Transfection Tumor Necrosis Factor-alpha