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Targeting in the System Described by Nonlinear Differential Equations

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Chinese Physics Letters 1996年第12期13卷 885-888页

作者： QIN Tuan-fa ni wan-sun DU Gong-huan CHEN Guang-zhi Institute of Acoustics and State Key Laboratory of Modern Acoustics Nanjing UniversityNanjing 210093 Department of Physics Guangxi UniversityNanning 530004

A method which directs trajectories to the predetermined continuous target orbits in the system described by nonlinear differential equations with perturbation of available system parameters and the conditions for achieving targeting is *** target orbits may be the unstable solution or even may not be the solution of the *** experiments are given in the periodically forced Brusselator.

关键词： system Nonlinear perturbation

Differential Gene Expression in Response to Drought Stress in Maize Seedling

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Agricultural Sciences in China 2009年第7期8卷 767-776页

作者： DENG Xiao-feng FU Feng-ling ni Na LI wan-chen Maize Research Institute Sichuan Agricultural University/Key Laboratory of Crop Genetic Resources and Improvement Ministry of Education Ya＇an 625014 P.R. China

To provide the useful information for the choice of molecular marker used in marker-assisted selection of drought tolerance, it is necessary to find out more candidate genes and fulfill the information gaps in gene expression regulation under drought stress. In this study, we isolated four differentially expressed cDNA fragments from leaves of a droughttolerant inbred line by suppression subtractive hybridization and reverse Northern hybridization, and validated their differential expression patterns among six inbred lines with different drought tolerance in response to drought stress by quantitative real-time PCR. Sequence similarity analysis indicated that two of four differentially expressed cDNA showed homology to gene DegP encoding trypsin-like serine protease, and gene PGAM-i encoding cofactor-independent phosphoglyceromutase, respectively. Expressions of the genes corresponding to four cDNA fragments was decreased at 6 h after drought stress treatment in most of the six inbred lines, and then returned to the control level with further stress in three of the tolerant inbred lines. The expression of the gene PGAM-i and the genes corresponding to fragments E4 and F4 were increased to a high level in tolerant inbred line 81565. In the two drought-sensitive inbred lines （Dan340 and ES40）, the expression of these genes was still down-regulated. The probable mechanisms of these genes in response to drought stress were discussed. These results indicated that the drought-tolerant inbred lines upregulated the expression of the drought-tolerant candidate genes, in contrast, drought-sensitive inbred lines downregulated the expression of the genes.

关键词： DegP drought tolerance expression pattern maize PGAM-i

Removal of Natural Organic Matter by Forward Osmosis Membrane： Flux Behaviour and Foulant Characterization

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Chemical Research in Chinese Universities 2015年第2期31卷 308-314页

作者： XIA Shengji YANG Ruilin ZHANG Xinhuan ni Muzi wan Yukun YAO Lijuan GAO Naiyun State Key Laboratory of Pollution Control and Resources Reuse Tongji University Shanghai 200092 P. R. China

Fouling of cellulose triacetate（CTA） forward osmosis（FO） membranes by natural organic matter（NOM） was studied by means of a cross-flow fiat-sheet forward osmosis membrane system. The NOM solution was employed as the feed solution（FS）, and a sodium chloride solution（3 tool/L） was used for the draw solution（DS）. The process was conducted at various temperatures and cross-flow velocities. The flux decline was investigated with 3 h forward osmosis operation. The substances absorbed on the membranes were cleaned by ultrasonic oscillation of the fouled membranes and were characterized by methodologies including fluorescence excitation-emission matrices （EEMs） and liquid chromatography with an organic carbon detector（LC-OCD）, and the variations of membrane properties were also investigated by Fourier transform infrared spectrometer（FTIR） and a contact angle meter. It was noted that the rejection efficiency of NOM is remarkable and that ultrasonic oscillation is an effective method to extract the NOM fouled on the CTA membranes after FO process. A higher cross-flow velocity and lower temperature benefit the anti-fouling capacity of the membrane significantly. Although humic substances accounted for the majority of the NOM, aromatic proteins and amino acids were the main fouling components on the membranes, with symbolic FTIR peaks at 2355, 1408 and 873 cm^-1. The present surface foulant made the membranes becoming more hydrophilic, as demonstrated by a significant decrease in contact angle（ranging from 20% to 46%） under all the operation conditions.

关键词： Drinking water Forward osmosis Fouling Natural organic matter Extraction Membrane flux

Cyanobacterial photo-driven mixotrophic metabolism and its advantages for biosynthesis

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Frontiers of Chemical Science and Engineering 2015年第3期9卷 308-316页

作者： ni wan Mary Abernathy Joseph Kuo-Hsiang Tang Yinjie J. Tang Le You Department of Energy Environmental and Chemical Engineering Washington University St. Louis MO 63130 USA Biodesign Institute Arizona State University Tempe AZ 85281 USA

Cyanobacterium offers a promising chassis for phototrophic production of renewable chemicals. Although engineered cyanobacteria can achieve similar product carbon yields as heterotrophic microbial hosts, their production rate and titer under photoautotrophic conditions are 10 to 100 folds lower than those in fast growing E. colt. Cyanobacterial factories face three indomitable bottlenecks. First, photosynthesis has limited ATP and NADPH generation rates. Second, CO2 fixation by ribulose-l,5-bisphosphate carboxylase/oxygenase （RuBisCO） has poor efficiency. Third, CO2 mass transfer and light supply are deficient within large photobioreac- tors. On the other hand, cyanobacteria may employ organic substrates to promote phototrophic cell growth, Nz fixation, and metabolite synthesis. The photo-fermenta- tions show enhanced photosynthesis, while CO2 loss from organic substrate degradation can be reused by the Calvin cycle. In addition, the plasticity of cyanobacterial path- ways （e.g., oxidative pentose phosphate pathway and the TCA cycle） has been recently revealed to facilitate the catabolism. The use of cyanobacteria as ＂green E. colt＂ could be a promising route to develop robust photobiorefineries.

关键词： CO2 mass transfer N2 fixation photosystem RuBisCO the TCA cycle

Microstructure evolution of loess under multiple collapsibility based on nuclear magnetic resonance and scanning electron microscopy

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Journal of Mountain Science 2021年第10期18卷 2612-2625页

作者： wanG Hai-man ni wan-kui YUAN Kang-ze LI Lan niE Yong-peng GUO Ye-xia College of Geological Engineering and Geomatics Chang’an UniversityXi'an 710054China Key Laboratory of Western China's Mineral Resources and Geological Engineering Ministry of EducationChang’an UniversityXi'an 710054China

In recent years, the acceleration of urbanization in loess areas has prompted frequent dismantling and reconstruction of old urban areas. Demolition and reconstruction of buildings involve multiple collapses of the foundation. To study microstructure evolution of loess under multiple collapsibility, this paper selects undisturbed loess samples from Guyuan, Northwest China for multiple compression tests. Using nuclear magnetic resonance(NMR) imaging and scanning electron microscopy(SEM) as auxiliary methods, a combination of qualitative and quantitative analyses was used to study the microstructure of loess samples before and after various number of collapses under different pressures. Results show that the loess does undergo multiple collapse under 200 kPa pressure. Pore is an important reason for loess collapse. The initial collapse comes primarily from the compression of macropores and mesopores, and the second collapse comes primarily from mesopore compression. The compression process of loess can be roughly divided into two stages. First, under the action of dissolution and compression, the relative displacement of soil particles occurs. Macropores and mesopores are destroyed first, generating small pores. Second, with increasing pressure and times of collapses, pore compression gradually transforms into small pore compression. During the first collapse, particle aggregates disintegrate due to water and pressure. However, with increasing times of collapses, the contact relationship between particles gradually changes from the point contact to face contact. Loess particles tend to gradually become rounded. The study of the microstructure provides the possibility to further reveal the mechanism of multiple collapsibility of loess.

关键词： Loess Multiple collapse Microstructure Nuclear magnetic resonance Pore volume

Effect of freeze-thaw cycles on uniaxial mechanical properties of cohesive coarse-grained soils

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Journal of Mountain Science 2019年第9期16卷 2159-2170页

作者： QU Yong-long CHEN Guo-liang niU Fu-jun ni wan-kui MU Yan-hu LUO Jing College of Geology Engineering and Geomatics Chang' an University Xi'an 710054 China China Gold Group Tibet Tyrone Mining Development Co. Ltd. Tibet 850000 China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China South China Institute of Geotechnical Engineering School of Civil Engineering and Transportation South China University of Technology Guangzhou 510641 China

Freeze-thaw cycles are closely related to the slope instability in high-altitude mountain regions. In this study, cohesive coarse-grained soils were collected from a high-altitude slope in the Qinghai–Tibet Plateau to study the effect of cyclic freeze-thaw on their uniaxial mechanical properties. The soil specimens were remolded with three dry densities and three moisture contents. Then, after performing a series of freeze-thaw tests in a closed system without water supply, the soil specimens were subjected to a uniaxial compression test. The results showed that the stress-strain curves of the tested soils mainly performed as strain-softening. The softening feature intensified with the increasing dry density but weakened with an increase in freeze-thaw cycles and moisture content. The uniaxial compressive strength, resilient modulus, residual strength and softening modulus decreased considerably with the increase of freeze-thaw cycles. After more than nine freeze-thaw cycles, these four parameters tended to be stable. These parameters increased with the increase of dry density and decreased with the increasing moisture content, except for the residual strength which did not exhibit any clear variation with an increase in moisture content. The residual strength, however, generally increased with an increase in dry density. The soil structural damage caused by frozen water expansion during the freeze-thaw is the major cause for the changes in mechanical behaviors of cohesive coarse-grained soils. With results in this study, the deterioration effect of freeze-thaw cycles on the mechanical properties of soils should be considered during the slope stability analysis in high-altitude mountain regions.

关键词： Freeze thaw cycles Residual strength Resilient modulus Softening modulus Uniaxial compressive strength Slope stability

Topoisomerase I Inhibition Radiosensitizing Hepatocellular Carcinoma by RNF144A-mediated DNA-PKcs Ubiquitination and Natural Killer Cell Cytotoxicity

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Journal of Clinical and Translational Hepatology 2023年第3期11卷 614-625页

作者： Chiao-Ling Tsai Po-Sheng Yang Feng-Ming Hsu Ann-Lii Cheng wan-ni Yu Jason Chia-Hsien Cheng Graduate Institute of Clinical Medicine National Taiwan University College of MedicineChina Taipei Division of Radiation Oncology Department of OncologyNational Taiwan University HospitalChina Taipei Department of General Surgery Mackay Memorial HospitalChina Taipei Graduate Institute of Oncology National Taiwan University College of MedicineChina Taipei Cancer Center National Taiwan UniversityChina Taipei Taiwan Liposome Company China Taipei

Background and Aims: Topoisomerase I (TOP1) partici-pates the repair of DNA double-strand breaks (DSBs) upon radiation therapy (RT). RNF144A mediates ubiquitination of catalytic subunit of DNA protein kinase (DNA-PKcs), a critical factor in DSB repair. This study aimed to investigate the natural killer (NK) cell-mediated radiosensitization with TOP1 inhibition and the mechanism by DNA-PKcs/RNF144A. Methods: In vitro synergism with TOP1i or cocultured NK cells and RT were evaluated in human hepatocellular car-cinoma (HCC) cell lines (Huh7/PLC5) by clonogenic surviv-als. Orthotopic xenografts were treated with Lipotecan and/or RT. Protein expression was analyzed by western blotting, immunoprecipitation, subcellular fractionation, and confocal microscopy. Results: Lipotecan/RT had a superior synergis-tic effect to RT on HCC cells. Combined RT/Lipotecan reduced the xenograft size by 7-fold than RT (p<0.05). Lipotecan caused more radiation-induced DNA damage and DNA-PKcs signaling. The expression of major histocompatibility com-plex class I-related chain A and B (MICA/B) on tumor cells is associated with the sensitivity to NK cell-mediated lysis. Cocultured NK and HCC cells with Lipotecan radiosensitized HCC cells/tissues with the expression of MICA/B. RNF144A increased more in Huh7 cells with combined RT/TOP1i, and reduced the prosurvival function of DNA-PKcs. The effect was reversed by inhibiting the ubiquitin/proteasome system. In comparison, RNF144A decreased through nuclear transloca-tion with the cumulated DNA-PKcs and radio-resistance of PLC5 cells. Conclusions: TOP1i reinforces NK cell-activated anti-HCC effect of RT through RNF144A mediated DNA-PKcs ubiquitination. RNF144A provides a reason for differentiating radiosensitization effect between HCC cells.

关键词： Hepatocellular carcinoma Radiotherapy DNA topoisomerase I Li-potecan RNF144A.

Study on the Application of Green Concept in Food Packaging Design

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Study on the Application of Green Concept in Food Packaging ...

作者： Lin LIU wan-ni GUO College of Art Design Hubei University of Technology

Discussing the food packaging design in terms of ecology,standards and requirements of green packaging and recycle,the paper aims at arousing the awareness of applying the idea of green packaging design,so as to avoid the over-design such as large interspace,too many package layers and complicated packaging on the *** packaging design needs to consider the relationship between production,sales and recycle,and application of the green packaging materials and reduction of the package *** on this,the materials that are biodegradable after discarding are developed,and then the food packaging that can reduce the energy consumption and cause no pollution to the environment are design.

关键词： Green concept Food packaging Over-design Recycle

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随机波动率费曼路径积分股指期权定价

物理学报 2019年第20期68卷 61-73页

作者：冯玲纪婉妮福州大学经济与管理学院

采用量子力学中的费曼路径积分方法,推导出了更符合市场一般化情形的随机波动率股指期权定价模型.在此基础上,以恒指期权为例进行实证研究预测30天的期权价格,同时将Heston模型作为对照组,并进行稳健性检验.研究结果表明,本文构建的股... 详细信息

采用量子力学中的费曼路径积分方法,推导出了更符合市场一般化情形的随机波动率股指期权定价模型.在此基础上,以恒指期权为例进行实证研究预测30天的期权价格,同时将Heston模型作为对照组,并进行稳健性检验.研究结果表明,本文构建的股指期权定价模型通过求解费曼定价核的数值解,进而在线性算法上直接实现股指期权价格的预测,相比于Heston模型利用特征函数的方法,不论是在相同到期日不同执行价格下还是在相同执行价格不同到期日下,定价精度显著提高.费曼路径积分作为量子金融的主要方法,本文的研究将为其进一步应用于金融衍生品定价提供参考.

关键词：费曼路径积分均值定价核随机波动率股指期权定价