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Approximate Solutions of Perturbed Nonlinear Schroedinger Equations

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Communications in Theoretical Physics 2007年第2X期48卷 227-231页

作者： CHENG Xue-Ping ye li-jun liN Ji Institute of Nonlinear Physics Zhejiang Normal University Jinhua 321004 China The Abdus Salam International Centre for Theoretical Physics Trieste 34139 Italy

By applying Lou＇s direct perturbation method to perturbed nonlinear Schroedinger equation and the critical nonlinear SchrSdinger equation with a small dispersion, their approximate analytical solutions including the zero-order and the first-order solutions are obtained. Based on these approximate solutions, the analytical forms of parameters of solitons are expressed and the effects of perturbations on solitons are briefly analyzed at the same time. In addition, the perturbed nonlinear Schroedinger equations is directly simulated by split-step Fourier method to check the validity of the direct perturbation method. It turns out that the analytical results given by the direct perturbation method are well supported by numerical calculations.

关键词： direct perturbation method perturbed nonlinear Schroedinger equation approximate solution

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多糖基离子凝胶研究进展

四川大学学报（自然科学版） 2024年第5期61卷 181-192页

作者：梁媛媛黄锴奇张乐任渊渊叶丽军李勇进杭州师范大学材料与化学化工学院杭州311121

离子凝胶在离子电导率和固液双相特性方面的独特优势而受到广泛关注.然而,采用人工合成聚合物所构筑的离子凝胶,存在着生物相容性差、生物可降解性不足、再生循环难度大、力学性能不足等问题,难以满足生态环境保护要求以及复杂应用场景... 详细信息

离子凝胶在离子电导率和固液双相特性方面的独特优势而受到广泛关注.然而,采用人工合成聚合物所构筑的离子凝胶,存在着生物相容性差、生物可降解性不足、再生循环难度大、力学性能不足等问题,难以满足生态环境保护要求以及复杂应用场景需要.以天然多糖为主要原料构筑的多糖基离子凝胶,不仅具有良好的生物相容性和生物可降解性,多糖分子特殊的分子结构和丰富的官能团还可赋予离子凝胶独特的理化性质和优异性能,在众多领域显示出巨大的应用潜力.本文对近年来基于多糖(纤维素、海藻酸盐、壳聚糖、黄原胶和环糊精等)设计制备的离子凝胶及其应用进行了综述,并对其发展前景进行了展望.

关键词：离子凝胶离子液体多糖

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微小核糖核酸-223在宫颈癌中的表达及意义

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中国妇幼保健 2024年第5期39卷 910-913页

作者：李康康叶丽君蒋亚萍台州市第一人民医院浙江台州318020

目的探讨微小核糖核酸-223(miR-223)在宫颈癌患者中的表达及其临床意义。方法选取45例宫颈癌患者的宫颈癌组织为宫颈癌组,癌旁组织为对照组。采用实时荧光定量PCR技术检测miR-223的表达水平,用SPSS 22.0软件对结果进行统计学分析。结果... 详细信息

目的探讨微小核糖核酸-223(miR-223)在宫颈癌患者中的表达及其临床意义。方法选取45例宫颈癌患者的宫颈癌组织为宫颈癌组,癌旁组织为对照组。采用实时荧光定量PCR技术检测miR-223的表达水平,用SPSS 22.0软件对结果进行统计学分析。结果宫颈癌组miR-223的表达量(1.848±0.630)显著高于对照组(1.027±0.359),差异有统计学意义(t=-7.591,P<0.05)。miR-223在Ⅲ~Ⅳ期患者的表达水平(2.370±0.341)显著高于Ⅰ~Ⅱ期患者的表达水平(1.301±0.311),低分化患者的表达水平(2.346±0.444)显著高于中分化和高分化患者的表达水平(1.598±0.560),有淋巴结转移患者的表达水平(2.125±0.567)显著高于无淋巴结转移组的表达水平(1.530±0.554),差异均有统计学意义(t=10.971、-4.508、3.558,均P<0.05)。miR-223对宫颈癌诊断的曲线下面积为0.825,具有较高的诊断效能。Kaplan-Meier生存曲线表明,与高表达组相比,miR-223低表达组患者的生存率明显提高(P<0.05)。结论miR-223在宫颈癌患者中表达升高,可作为宫颈癌诊断的分子生物学标志物。

关键词：微小核糖核酸-223 宫颈癌表达

结肠镜息肉切除术联合地衣芽孢杆菌活菌对结肠息肉患者的临床效果及对肠道菌群、预后的影响

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医学信息 2024年第15期37卷 79-82页

作者：叶利君谢建生洪艳芬婺源县人民医院消化内科婺源县人民医院药剂科

目的研究地衣芽孢杆菌活菌胶囊在结肠镜下高频电凝电切术患者中的临床效果及对肠道菌群、预后的影响。方法选取2021年1月-2022年12月于我院治疗的80例结肠息肉术后患者为研究对象，采用随机数字表法分为对照组(n=40)和观察组(n=40)，... 详细信息

目的研究地衣芽孢杆菌活菌胶囊在结肠镜下高频电凝电切术患者中的临床效果及对肠道菌群、预后的影响。方法选取2021年1月-2022年12月于我院治疗的80例结肠息肉术后患者为研究对象，采用随机数字表法分为对照组(n=40)和观察组(n=40)，对照组采用结肠镜下高频电凝电切术治疗，观察组在对照组基础上给予地衣芽孢杆菌活菌胶囊治疗，比较两组临床效果、肠道菌群、并发症发生率、6个月后复发率及生活质量水平。结果观察组治疗总有效率为95.00%，高于对照组的82.50%(P<0.05)；两组治疗后双歧杆菌、乳杆菌计数高于治疗前，大肠杆菌低于治疗前，且观察组双歧杆菌、乳酸菌计数高于对照组，大肠杆菌计数低于对照组(P<0.05)；观察组并发症发生率为12.50%，低于对照组的27.50%(P<0.05)；随访6个月，观察组复发率为5.00%，低于对照组的17.50%(P<0.05)；两组治疗后生活质量各维度评分均高于治疗前，且观察组高于对照组(P<0.05)。结论地衣芽孢杆菌活菌胶囊在结肠镜下高频电凝电切术患者中具有较高的临床效果，可促进肠道菌群恢复，降低并发症发生率及复发率，提高患者生活质量水平，值得临床加以应用。

关键词：地衣芽孢杆菌活菌胶囊结肠息肉结肠镜下高频电凝电切术肠道菌群

Perturbative Painleve Analysis of General KdV System and Its Exact Soliton Solutions

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Communications in Theoretical Physics 2005年第8期44卷 197-202页

作者： liN Ji ye li-jun li Hua-Mei Institute of Nonlinear Physics, Zhejiang Normal University, Jinhua 321004, China Institute of Nonlinear Physics Zhejiang Normal University

Using the standard Painlevé analysis ad the perturbative method,the Painlevé test for the logarithmicbranch is investigated. Nine arbitrary functions are obtained and the B cklund transformation of the logarithmic b... 详细信息

关键词： Painlevé analysis perturbative method Jacobi elliptic solution

Spatially explicit reconstruction of cropland cover in Europe from AD 1800 to 2000

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Science China Earth Sciences 2024年第9期67卷 2953-2971页

作者： jun li Yu ye Xiuqi FANG Diyang ZHANG Zhilei WU Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China College of Geographical Science Qinghai Normal UniversityXining 810016China

One of the challenges in global change research is the significant uncertainty in global historical land use and land cover(LUCC)datasets,which are widely used as foundational *** addition to the regional cropland area reconstructions,improving the grid allocation method is another feasible way to raise the reliability of historical LUCC *** this study,an integrated reconstruction of the national cropland areas over the past 200 years was developed for 36 European *** that,the allocation algorithm was built using physiogeographic variables and historical city sites for accounting for land suitability and cultivation preferences,***,cropland data in Europe with a spatial resolution of 5′×5′at five time sections from AD 1800 to 2000 were generated using the optimal allocation algorithm in accordance with the stages of the regional *** results were as follows:(1)The dominant factors governing the distribution of croplands in Europe vary at different agricultural stages,but the results can be merged *** suitability was more optimal for allocation during the modern agricultural stage(AD 1950 and 2000);the priority index combined with land suitability and cultivation preference was more reasonable for allocation during the traditional agricultural stage(AD 1800).The average of the allocations by priority index and the land suitability could be adopted as the allocation results during the transitional stage(AD 1850 and 1900)because the grids for absolute differences within±10 and±20 percentage points between the results obtained from the above two allocations were above 80% and 95%,respectively,which means the two allocation results could be merged.(2)Over the past 200 years,the total cropland area in Europe first increased to a peak in AD 1900 and then ***,the centre of the higher cropland fraction shifted from the western part of Europe in AD 1800 to the eastern part of the continent after AD 1950.(3)

关键词： Land use and land cover change Historical cropland Gridding allocation Europe Past 200 years

Cloning and Characterization of a Novel cDNA Encoding Late Embryogenesis-Abundant Protein 5 like (LEA-5) Gene from Cara Cara Navel Orange Fruit (Citrus sinensis Osbeck)

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Agricultural Sciences in China 2006年第4期5卷 272-276页

作者： TAO Neng-guo ye jun-li XU Juan DENG Xiu-xin National Key Laboratory of Crop Genetic Improvement National Center of Crop Molecular Breeding Huazhong Agricultural University Wuhan 430070 P.R.China

LEA5 gene was postulated related with both stress and hormone responses. In an attempt to find genes exclusively expressed during fruit ripening of Cara Cara navel orange, a novel cDNA clone encoding late embryogenesis-abundant protein 5 like gene （CitLEA5-1） was obtained. It was 582 bp in length, containing 97 deduced amino acids. Compared with the stress-induced LEA5 from leaves of Citrus sinensis, CitLEA5-1 had a shorter 3′ untranslated region （UTR）. Semi-quantitative RT-PCR analysis revealed that CitLEA5-1 was transcriptional regulated during fruit ripening of Cara Cara navel orange.

关键词： Citrus cloning characterization late embryogenesis-abundant protein

Numerical Simulation on Radon Retardation Behavior of Covering Floats in Radon-Containing Water

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Biomedical and Environmental Sciences 2024年第4期37卷 406-417页

作者： liU Shu Yuan ZHANG li ye Yong jun DING Ku Ke National Institute for Radiological Protection Chinese Center for Disease Control and PreventionBeijing 100088China Office for Public Health Management Chinese Center for Disease Control and PreventionBeijing 102206China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001HunanChina

Objective This study aimed to efficiently reduce the release of radon from water bodies to protect the *** Based on the sizes of the experimental setup and modular float,computational fluid dynamics(CFD)was used to assess the impact of the area coverage rate,immersion depth,diffusion coefficient,and radon transfer velocity at the gas–liquid interface on radon migration and exhalation of radon-containing *** on the numerical simulation results,an estimation model for the radon retardation rate was *** effectiveness of the CFD simulation was evaluated by comparing the experimental and simulated variation values of the radon retardation rate with the coverage area *** The effect of radon transfer velocity on radon retardation in water bodies was minor and insignificant according to the appropriate value;therefore,an estimation model of the radon retardation rate of the coverage of a radon-containing water body was constructed using the synergistic impacts of three factors:area coverage rate,immersion depth,and diffusion *** deviation between the experimental and simulated results was<4.3%.Conclusion Based on the numerical simulation conditions,an estimation model of the radon retardation rate of covering floats in water bodies under the synergistic effect of multiple factors was obtained,which provides a reference for designing covering floats for radon retardation in radoncontaining water.

关键词： Radon-containing water Radon retardation rate CFD Coverage experiment Optimized design

Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models

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Nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： Jia-Hao Wang Rui Qiu An-Kang Hu ye-Qi liu Zhen Wu Hui Zhang jun-li li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint Institute of Tsinghua University Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation