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Sharp Threshold of Global Existence for a Nonlocal Nonlinear Schrdinger System in R^(3)

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Chinese Annals of Mathematics,Series B 2019年第1期40卷 131-160页

作者： Zaihui gan Xin JIANG jing li Center for Applied Mathematics Tianjin University School of Preparatory Education Xinjiang Normal University

In this paper, the authors investigate the sharp threshold of a three-dimensional nonlocal nonlinear Schr¨odinger system. It is a coupled system which provides the mathematical modeling of the spontaneous generation of a magnetic field in a cold plasma under the subsonic limit. The main difficulty of the proof lies in exploring the inner structure of the system due to the fact that the nonlocal effect may bring some hinderance for establishing the conservation quantities of the mass and of the energy, constructing the corresponding variational structure, and deriving the key estimates to gain the expected result. To overcome this, the authors must establish local well-posedness theory, and set up suitable variational structure depending crucially on the inner structure of the system under study, which leads to define proper functionals and a constrained variational problem. By building up two invariant manifolds and then making a priori estimates for these nonlocal terms, the authors figure out a sharp threshold of global existence for the system under consideration.

关键词： Nonlocal nonlinear Schrödinger system Sharp threshold Blow-up Global existence

Driving effect of P16 methylation on telomerase reverse transcriptase-mediated immortalization and transformation of normal human fibroblasts

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中华医学杂志(英文版) 2025年第03期

作者： Zhang Xuehong li Paiyun gan Ying Xiang Shengyan Gu liankun Zhou jing Zhou Xiaorui Wu Peihuang Zhang Baozhen Deng Dajun Key Laboratory of Carcinogenesis and Translational Research (MOE/Beijing) Division of Etiology Peking University Cancer Hospital and Institute Beijing China Division of Etiology Beijing Cancer Hospital Beijing China Radiation Oncology Department Tianjin Medical University General Hospital Tianjin China Department of Biomedical Engineering Peking University Cancer Hospital and Institute Beijing China

Background: P16 inactivation is frequently accompanied by telomerase reverse transcriptase (TERT) amplification in human cancer genomes.P16 inactivation by DNA methylation often occurs automatically during immortalization of normal cells byTERT. However, direct evidence remains to be obtained to support the causal effect of epigenetic changes, such asP16 methylation, on cancer development. This study aimed to provide experimental evidence thatP16 methylation directly drives cancer ***: A zinc finger protein-basedP16-specific DNA methyltransferase (P16-Dnmt) vector containing a "Tet-On" switch was used to induce extensive methylation ofP16 CpG islands in normal human fibroblast CCD-18Co cells. Battery assays were used to evaluate cell immortalization and transformation throughout their lifespan. Cell subcloning and DNA barcoding were used to track the diversity of cell ***: Leaking P16-Dnmt expression (without doxycycline-induction) could specifically inactivateP16 expression by DNA methylation.P16 methylation only promoted proliferation and prolonged lifespan but did not induce immortalization of CCD-18Co cells. Notably, cell immortalization, loss of contact inhibition, and anchorage-independent growth were always prevalent in P16-Dnmt&TERT cells, indicating cell transformation. In contrast, almost all TERT cells died in the replicative crisis. Only a few TERT cells recovered from the crisis, in which spontaneousP16 inactivation by DNA methylation occurred. Furthermore, the subclone formation capacity of P16-Dnmt&TERT cells was two-fold that of TERT cells. DNA barcoding analysis showed that the diversity of the P16-Dnmt&TERT cell population was much greater than that of the TERT cell ***: P16 methylation drivesTERT-mediated immortalization and transformation of normal human cells that may contribute to cancer development.

关键词： P16 methylation Telomerase reverse transcriptase Immortalization Transformation Barcode lineage tracking Human fibroblasts

用于无损离子操纵结构的双极性射频电源的研制

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质谱学报 2025年第1期46卷 97-105页

作者：刘青许润泽张允晶李灵锋李鹏苏州大学电子信息学院江苏苏州215006

无损离子操纵结构(structures for lossless ion manipulations,SliM)是一种在特殊背景气体下,利用静电场、射频电场、离子驱动电场共同作用实现对气相离子无损传输的新结构,在物质传输和分离方面有着广阔的应用前景。为了充分发挥SliM... 详细信息

无损离子操纵结构(structures for lossless ion manipulations,SliM)是一种在特殊背景气体下,利用静电场、射频电场、离子驱动电场共同作用实现对气相离子无损传输的新结构,在物质传输和分离方面有着广阔的应用前景。为了充分发挥SliM在体积和成本上的优势,本研究研制了一款体积小、结构紧凑、成本经济的高频高压双极性射频(radio frequency,RF)电源。该电源使用隔离模块实现控制电路与功率电路的电气隔离,并采用以gan金属-氧化物-半导体场效应管(MOSFET)为核心的半桥电路作为输出级。针对SliM的容性负载特性,利用电阻-电感-电容(RLC)电路的滤波特性,实现双极性正弦脉冲电压的输出。经测试,该电源可输出频率1 MHz、峰-峰值420 V(±210 V)的双极性正弦射频高压信号。在实验室自建的基于行波(traveling wave,TW)的无损离子操纵结构(TW-SliM)迁移谱实验平台上,以甲基膦酸二甲酯(DMMP)为样本,深入探究了射频电源幅值及频率对小分子离子传输效率的影响。结果表明,射频电源幅值及频率均会对TW-SliM结构的离子传输效率产生影响,并存在1个最优值范围,这与COMSOL的仿真结果相吻合。该射频电源能够有效支持TW-SliM平台的稳定运行,对推动基于SliM的小分子迁移谱技术的小型化和便携化研发具有重要价值。

关键词：无损离子操纵结构(SliM) 射频电源半桥电路隔离电路

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Efficacy and safety of activating blood circulation and removing blood stasis of Traditional Chinese Medicine for managing renal fibrosis in patients with chronic kidney disease:a systematic review and Meta-analysis

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Journal of Traditional Chinese Medicine 2023年第3期43卷 429-440页

作者： LUO Xin XIE jing HUANG li gan Wenfan CHEN Ming Hospital of Chengdu University of Traditional Chinese Medicine Chengdu 610072China Chengdu University of Traditional Chinese Medicine Chengdu 610075China

OBJECTIVE:To evaluate the efficacy and safety of activating blood circulation and removing blood stasis in terms of Traditional Chinese Medicine(TCM) for managing renal fibrosis(RF) in patients with chronic kidney disease(CKD).METHODS:We searched randomized controlled trials(RCTs) from eight ***:Sixteen eligible studies with 1,356 participants were included in this *** to treatment with Western Medicine(WM) alone,the combined treatment with activating blood circulation and removing blood stasis in terms of TCM(ARTCM) and WM to manage RF in patients with CKD significantly ameliorated type Ⅳ collagen(C-Ⅳ)(SMD:-2.17,95% CI:3.01 to-1.34),type Ⅲ procollagen(PC-Ⅲ)(SMD:-1.08,95% CI:-1.64 to-0.53),laminin(LN)(SMD:-1.28,95% CI:-1.65 to-0.90),transforming growth factor β 1(TGF-β1)(SMD:-0.65,95% CI:-1.18 to-0.12),serum creatinine(Scr)(SMD:-1.36,95% CI:-1.85 to-0.87),blood urea nitrogen(BUN)(MD:-1.51,95% CI:-2.59 to-0.43),and 24 h urine protein(24h Upro)(SMD:-1.23;95% CI:-1.96 to-0.50).The level of hyaluronic acid(HA) was similar in both types of treatment(SMD:-0.74,95% CI:-1.91 to 0.44).The subgroup analysis showed that the duration of 8 weeks might affect the concentration of C-Ⅳ,PC-Ⅲ,and LN(P lication bias for the reports on Scr(P = 0.001),C-Ⅳ(P = 0.001),PC-Ⅲ(P = 0.026),and LN(P = 0.030) and no publication bias for the reports on BUN(P = 0.293).The quality of evidence varied from low to very ***:The combined treatment using ARTCM and WM to manage RF in patients with CKD has some advantages over treatment with WM ***-quality RCTs need to be conducted for the strong support.

关键词： Medicine Chinese traditional activating blood circulation and removing blood stasis renal fibrosis efficacy safety Meta-analysis systematic review

Free control of far-field scattering angle of transmission terahertz wave using multilayer split-ring resonators'metasurfaces

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Frontiers of physics 2020年第6期15卷 125-132页

作者： Ying Tian Xufeng jing Haiyong gan Chenxia li Zhi Hong Institute of Optoelectronic Technology China Jiliang UniversityHangzhou 310018China National Institute of Metrology Beijing 102200China

To enhance transmission eficiency of Pancharatnam Berry(PB)phase metasurfaces,multilayer split-ring resonators were proposed to develop encoding *** per the generalized Snell's law,the deflection angle of the PB phase encoding metasurfaces depends on the metasurface period's ***,it is impossible to design an infinitesimal metasurface unit;consequently,the continuous transmission scattering angle cannot be *** digital signal processing,this study introduces the Fourier convolution principle on encoding metasurface sequences to freely control the trausmitted scattering *** addition and subtraction operations between two diferent encoding sequences were then performed to achieve the continuous variation of the scattering ***,we established that the Fourier convolution principle can be applied to the checkerboard coded metasur-faces.

关键词： metamaterial metasurface scattering Fourier convolution

Acupuncture and moxibustion for treatment of Crohn’s disease:A brief review

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World Journal of Gastroenterology 2022年第25期28卷 3001-3003页

作者： jing Xie Yan Huang Huan-gan Wu jing li Department of Acupuncture Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China Shanghai Research Institute of Acupuncture and Meridian Shanghai University of Traditional Chinese MedicineShanghai 200030China

Crohn’s disease(CD)is a kind of intestinal inflammatory disease that can affect any part of the gastrointestinal tract and the incidence rate of CD is gradually increasing *** and moxibustion have unique curative eff... 详细信息

关键词： Crohn’s disease Acupuncture Moxibustion Treatment Review

原子吸收光谱法测定矿石中Au的分析技术及最优化模型研究

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光谱学与光谱分析 2025年第2期45卷 426-433页

作者：王鹏门倩妮甘黎明白金峰王啸井斌强寇少磊刘慧蓝何涛刘玖芬中国地质调查局西安矿产资源调查中心陕西西安710100 中国地质调查局金矿勘查技术创新中心陕西西安710100 中国地质调查局自然资源综合调查指挥中心北京100055 中国地质科学院地球物理地球化学勘查研究所河北廊坊065000 中国矿业报社北京100037 中国地质大学(北京) 北京100083

矿石中Au通常以颗粒金或者晶格金的形式存在,在不同类型的金矿石中赋存状态不同,其特殊的延展性引起的颗粒效应对于Au样品的分析技术带来挑战,并且其制备流程要素繁多且不易控制,直接影响Au分析的准确性和稳定性。以矿石中金元素为研究... 详细信息

矿石中Au通常以颗粒金或者晶格金的形式存在,在不同类型的金矿石中赋存状态不同,其特殊的延展性引起的颗粒效应对于Au样品的分析技术带来挑战,并且其制备流程要素繁多且不易控制,直接影响Au分析的准确性和稳定性。以矿石中金元素为研究对象,建立泡塑吸附-原子吸收光谱法测定矿石中Au的分析方法,针对样品测试流程中的关键要素进行定性判断和定量计算,提出基于灰色关联度-响应曲面法的最优化模型。讨论样品分析技术中焙烧、消解、富集和解脱等重要环节,确定焙烧方式、消解酸度、富集时间和硫脲浓度为优化要素,设计正交试验并进行相关性分析,计算灰色关联系数并进行极差确定,定性判断各优化要素的显著性。中心组合设计结合响应曲面法原理制作显著水平表,建立二次多项式回归方程的预测模型并进行显著性分析,绘制三维响应曲面图和二维等高线图对实验数据进行拟合分析,确定最优化模型参数焙烧方式、消解酸度、富集时间和硫脲浓度分别为阶梯式分段焙烧、10.58%、40.00 min、11.65 g·L^(-1)。实验结果表明,在最优化模型条件下对金矿石国家一级标准物质进行制备测试,其方法检出限为0.021,测定下限为0.077,加标回收率为91.6%~104.5%,其正确度和精密度均符合GB/T 20899.2—2019质量控制要求;同时对陕西西秦岭地区和甘肃梅川地区外检样品进行方法验证比对,其相对偏差不超过10%且评价结果均为优秀,表明该检测优化模型方法在实际样品中的应用依然准确可靠,具备正确性和科学性。该研究对于地质矿产实验室快速、准确、简便分析Au元素提出新方法,为检验检测领域中优化多目标参数组合的课题提供了新的思路,同时为新一轮战略找矿行动的准确测试贡献力量。

关键词：金原子吸收光谱法灰色关联度响应曲面法中心组合设计质量控制

A new insight into iron ore oxidized pellets prepared by steel belt roasting process

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钢铁研究学报（英文版） 2024年第12期31卷 2903-2914页

作者： Tao jing Hao Lv Min gan Xiao-hui Fan jing li You-xun Dai Zhuo-qi liu Shi-xian li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Zhongye Changtian International Engineering Co. Ltd.Changsha 410205HunanChina School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Zhongye Changtian International Engineering Co. Ltd.Changsha 410205HunanChina

The steel belt roasting process has the advantages of low cost,small footprint,and high thermal efficiency,making it widely used in the smelting of ferroalloys such as ferrochrome,ferromanganese,and ***,its appli-cation in preparing iron ore oxidized pellets has not been sufficiently *** optimal thermal process conditions for magnesium-containing oxidized pellet preparation by steel belt roasting machine were investigated based on the roasting properties of high-magnesium iron concentrate and typical iron *** results indicate that,for the blending scheme of 70 wt.％high-magnesium iron concentrate and 30 wt.％typical iron concentrate,the appropriate preheating temperature for pellets is 950-975 ℃ and the suitable roasting temperature is 1250-1275 ℃,during which the com-pressive strength of pellets can exceed 2500 N *** the steel belt roasting process,SO2 is primarily released in the preheating zone,and the maximum exhaust gas temperature in the roasting zone can reach 637 ℃.High-temperature sulfur-containing exhaust gas causes oxidation corrosion,sulfide corrosion,and deformation of the steel *** enhance the steel belt longevity,it is recommended to appropriately reduce the wind velocity in the preheating zone and roasting zone,while also decreasing the ratio of pellet bed height to hearth layer *** adopting the system of"low wind velocity,thin pellet bed,fast steel belt speed,"the exhaust gas temperature can be reduced to 463 ℃.The prepared pellet maintains a compressive strength of 2607 N pellet-1 and exhibits excellent metallurgical properties.

关键词： Steel belt roasting process High-magnesium iron concentrate Oxidized pellet Compressive strength Exhaust gas temperature

Rapid recovery of polycrystalline silicon from kerf loss slurry using double-layer organic solvent sedimentation method

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International Journal of Minerals,Metallurgy and Materials 2013年第10期20卷 947-952页

作者： Peng-fei Xing jing Guo Yan-xin Zhuang Feng li gan-feng Tu School of Materials and Metallurgy Northeastern University Xinjiang Joinworld Co. Ltd.Xinjiang Uygur Autonomous Region Key Laboratory of Electromagnetic Processing of Materials Northeastern University

The rapid development of photovoltaic （PV） industries has led to a shortage of silicon feedstock. However, more than 40% silicon goes into slurry wastes due to the kerf loss in the wafer slicing process. To effectively recycle polycrystalline silicon from the kerf loss slurry, an innovative double-layer organic solvent sedimentation process was presented in the paper. The sedimentation velocities of Si and SiC particles in some organic solvents were investigated. Considering the polarity, viscosity, and density of solvents, the chloroepoxy propane and carbon tetrachloride were selected to separate Si and SiC particles. It is found that Si and SiC particles in the slurry waste can be successfully separated by the double-layer organic solvent sedimentation method, which can greatly reduce the sedimentation time and improve the purity of obtained Si-rich and SiC-rich powders. The obtained Si-rich powders consist of 95.04% Si, and the cast Si ingot has 99.06% Si.

关键词： silicon purification sedimentation organic solvents waste utilization