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nano Research 2018年第8期11卷 4102-4110页

作者： zhi Du Yijia Guan nan Gao Jinsong Ren xiaogang Qu Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of AppliedChemistry Chinese Academy of Sciences Changchun 130022 China University of Chinese Academy of Sciences Beijing 100039 China

Recent clinical and epidemiological research has shown that insulin is associated with the pathological mechanisms of Alzheimer＇s disease （AD） and can protect against the oxidative stress triggered by amyloidq3 peptide （Aβ3）. Herein, we present a systematic study on how the cross-fibrillation of insulin and Aβ is influenced by the surface chirality of an interface designed to mimic their aggregation on the cytomembrane. Intriguingly, the surface chirality strongly affected the aggregation kinetics, structure, morphologβ and cellular responses of the cross-aggregates of insulin and Aβ. On a D-phenylalanine- modified surface, Aβ induced insulin to co-aggregate into β-sheet-rich fibrils and cross-fibrils that showed a pronounced cellular toxicity. However, on an L-phenylalanine-modified surface, insulin and Aβ3 formed non-toxic amorphous aggregates. Our work indicates that surface chirality can influence the cross- fibrillation of Aβ and insulin as well as the cytotoxicity of their aggregates.

关键词： Alzheimer's disease insulin,amyloid β-peptides artificial biointerfaces chirality

On the Terai-Jésmanowicz Conjecture

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Acta Mathematica Sinica,English Series 2008年第12期24卷 2061-2064页

作者： Jian Ye xia Ping zhi YUAN Department of Basic Science Guangdong University of Finance Guangzhou 510521 P. R. China School of Mathematics South China Normal University Guangzhou 510631 P. R. China

In this paper, we prove that if a, b and c are pairwise coprime positive integers such that a^2＋b^2=c^r,a〉b,a≡3 （mod4）,b≡2 （mod4） and c-1 is not a square, thena a^x＋b^y=c^z has only the positive integer solution （x, y, z） = （2, 2, r）. Let m and r be positive integers with 2｜m and 2 r, define the integers Ur, Vr by （m ＋√-1）^r=Vr＋Ur√-1. If a = ｜Ur｜,b=｜Vr｜,c = m^2＋1 with m ≡ 2 （mod 4）,a ≡ 3 （mod 4）, and if r 〈 m/√1.5log3（m^2＋1）-1, then a^x ＋ b^y = c^z has only the positive integer solution （x,y, z） = （2, 2, r）. The argument here is elementary.

关键词： exponential diophantine equations Terai-Jesmanowicz conjecture Lucas sequences

Hamiltonicity of 4-connected Graphs

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Acta Mathematica Sinica,English Series 2010年第4期26卷 699-710页

作者： Hao LI Feng TIAN zhi xia XU LRI Univ. Paris-sud 11 and CNRS Orsay F-91405 France School of Mathematics and Statistics Lanzhou University Lanzhou 730000 P. R. China Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P. R. China Center for Combinatorics and LPMC-TJKLC Nankai University Tianjin 300071 P. R. China Department of Mathematics Tianjin Polytechnic University Tianjin 300160 P. R. China

Let σk（G） denote the minimum degree sum of k independent vertices in G and α（G） denote the number of the vertices of a maximum independent set of G. In this paper we prove that if G is a 4-connected graph of ord... 详细信息

关键词： k-connected Hamiltonian insertible vertex crossing diagonals

Clean Monascus pigments production from Chinese rice wine wastes through submerged fermentation

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Food Bioscience 2023年第2期52卷 843-850页

作者： Mengfei Long Yongchao Cai nan Zheng zhi Lu Wentao Cao Yaxian Li xiaomei Pei Osire Tolbert xiaole xia The Key Laboratory of Industrial Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxi214122China Infinitus(China)Co.Ltd. Guangzhou510665China Faculty of Biology Shenzhen MSU-BIT UniversityShenzhen518172China

The potential for Monascus pigments(MPs)production in a mixture of Chinese rice wine lees,soaked rice wastewater and broken rice was *** production reached 120.1 U/mL with optimal solid-liquid ratio of culture medium 1:10 and 20 g/L broken rice addition at shake flask *** further explored the effects of stirring speed on MPs production in 7.5 L agitated *** stirring speed had a great impact on cell morphology and the maximum MPs concentration and yield were 128.4 U/mL and 8174 U/g respectively at 400 *** soluble chemical oxygen demand for the soaked rice wastewater decreased by 78.7%,which was mainly due to the intake of carbohydrates,organic acids and amino ***,a simultaneous fermentation process and production system with two-stage stirring speed control strategy was further developed in the 50 L pilot scale,in which the MPs production reached 158.9 U/***,Chinese rice wine wastes were fully utilized without addition of organic solvents during the process and no generation of new *** results showed that Monascus was capable of converting Chinese rice wine wastes into natural pigments by submerged fermentation,which could provide an economic and environmentally friendly approach to reduce the cost of wastes treatment as well as high-value utilization.

关键词： Monascus pigments Submerged fermentation Chinese rice wine wastes Pilot scale fermentation Simultaneous fermentation process and production system

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与图像内容无关的聚焦程度评价方法

西安交通大学学报 2025年第1期59卷 116-124页

作者：夏晓华柴玉琳岳鹏举杨治秦绪芳长安大学道路施工技术与装备教育部重点实验室西安710000

针对现有的聚焦程度评价方法在图像场景内容改变时不能正确评价图像聚焦程度的问题,基于“分类+拟合”的思想,提出了一种与高斯模糊标准差完全等价的图像聚焦程度评价方法。首先,建立了以有限高斯模糊标准差为标记的图像聚焦程度分类数... 详细信息

针对现有的聚焦程度评价方法在图像场景内容改变时不能正确评价图像聚焦程度的问题,基于“分类+拟合”的思想,提出了一种与高斯模糊标准差完全等价的图像聚焦程度评价方法。首先,建立了以有限高斯模糊标准差为标记的图像聚焦程度分类数据集;然后,构建了用于提取图像高斯模糊标准差分类分数的非对称核卷积神经网络(AKC-net);最后,采用三次样条插值函数拟合AKC-net全连接层输出的分类分数以及对应的高斯模糊标准差,以最大分数对应的标准差作为图像的聚焦程度评价结果,并在Waterloo数据集和实际拍摄图像上分别进行仿真实验和实拍实验。结果表明:所提方法在不同聚焦图像上分类的平均准确率可达到97.7%,得到的评价结果与高斯模糊标准差真值的均方根误差和平均绝对误差均小于0.07,且实际拍摄图像的聚焦测度值与图像内容无关,实现了图像聚焦程度的绝对评价。

关键词：聚焦程度评价高斯模糊标准差非对称核卷积神经网络三次样条插值

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Modified Two-Degrees-of-Freedom Internal Model Control for Non-Square Systems with Multiple Time Delays

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Journal of Harbin Institute of Technology(New Series) 2014年第2期21卷 122-128页

作者： Jian-Chang Liu nan Chen xia Yu School of Information Science and Technology Northeastern University

A modified two-degrees-of-freedom( M-TDOF) internal model control( IMC) method is proposed for non-square systems with multiple time delays and right-half-plane( RHP) zeros. In this method,pseudo-inverse is introduced to design the internal model controller,and a desired closed-loop transfer function is designed to eliminate the unrealizable factors of the derived controller. In addition,set-point tracking and load-disturbance rejection of each process are separately controlled by two controllers. The simulation results show that in addition to high decoupling performance and robustness,the proposed control method also effectively improves loaddisturbance rejection and simultaneously optimizes the input tracking performance and disturbance rejection performance by selecting the parameters of controllers. Furthermore,the higher tolerance of model mismatch is achieved in this paper.

关键词： non-square system two degrees of freedom internal model control

EFFECT OF SURFACTANTS ON Ni-TiN nanOCOMPOSITE COATINGS PREPARED BY ULTRASONIC ELECTRODEPOSlTION

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Chinese Journal of Mechanical Engineering 2008年第3期21卷 84-86页

作者： xia Fafeng JIA Zhenyuan WU Menghua LI zhi School of Mechanical Engineenng Dalian University of Technology Dalian 116023 China School of Mechanical Engineenng Dalian University Dalian 116622 China

Ni-TiN nanocomposite coatings were prepared by ultrasonic electrodeposition, and the effects of the surfactants on the coatings were investigated and the microstructure and micro rigidity of the coatings were characterized. Samples were also submitted to corrosion tests in 3% NaCl solution. The results showed that the surfactants had great effects on Ni-TiN nanocomposite coatings. The composite coatings prepared by ultrasonic electrodeposition with the surfactants were better than that of the coatings prepared without surfactants. The favorable properties of Ni-TiN nanocomposite coatings were prepared with the mixing of the non-ion and positive ion surfactants. The concentration of the mixing was 80 mg/L, and the ratio of the non-ion and positive ion surfactants was 1： 2.

关键词： Effect Surfactant Ni-TiN nanocomposite coating

ULTRASONIC PROPAGATIONS IN COMPOSITIONAL MODULATED STRUCTURES(CMS)

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Chinese Physics Letters 1984年第2期1卷 77-80页

作者： ZOU nan-zhi GONG Chang-de Institute of Solid State Physics Nanjing University

The dynamic equation of acoustic vibration in CMS can be obtained by means of the mean field *** propagation features in CMS are discussed,while the corresponding dispersion law,forbidden bands of the sound waves also... 详细信息

关键词： CMS dispersion sound

DFT Study on Homolytic Dissociation Enthalpies of C-I Bonds

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Chinese Journal of Chemical Physics 2013年第5期26卷 541-548,I0003页

作者： Wen-rui Zheng zhi-chong Chen Wu-xia Xu Department of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620 China

The C-I bond dissociation enthalpies （BDE） of various organic iodides were calculated using high-level theoretical methods including MP2 and CCSD（T） with extrapolated basis set as well as a number of density functional theory methods. After systematic evaluation of the theoretical results against available experimental C-I BDEs, it was found that the MPW LYPIM method gave the lowest root mean square error. We, therefore, used this method to examine the substituent effects on different categories of C（sp3）-I and C（sp2）-I bonds. Fur thermore, the remote substituent effects on the C-I BDEs of substituted iodobenzenes and substituted （iodomethyl）benzenes were also investigated at the same level. The C-I BDEs of typical heteroaromatic iodides including five-membered and six-membered heterocyclic iodides were also examined.

关键词： C'I bond Bond dissociation enthalpy Density functional theory

Comparison of three transgenic Bt rice lines for insecticidal protein expression and resistance against a target pest, Chilo suppressalis （Lepidoptera： Crambidae）

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Insect Science 2016年第1期23卷 78-87页

作者： Ya-nan Wang Kai-Qie Ke Yun-He Li Lan-zhi Han Yan-Min Liu Hong-xia Hua Yu-Fa Peng State Key Laboratory for Biology of Plant Disease and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural ScienceBeUing 100193 College of Plant Science & Technology Huazhong Agricultural University Wuhan 430070 China

Two transgenic rice lines （T2A-1 and T1C-19b） expressing cry2A and crylC genes, respectively, were developed in China, targeting lepidopteran pests including Chilo suppressalis （Walker）（Lepidoptera： Crambidae）. The seasonal expression of Cry proteins in different tissues of the rice lines and their resistance to C. suppressalis were assessed in comparison to a Bt rice line expressing a crylAb/Ac fusion gene, Huahui 1, which has been granted a biosafety certificate. In general, levels of Cry proteins were T2A- 1 〉 Huahui I 〉 T1C-19b among rice lines, and leaf 〉 stern 〉 root among rice tissues. The expression patterns of Cry protein in the rice line plants were similar： higher level at early stages than at later stages with an exception that high Cry 1C level in T 1 C- 19b stems at the maturing stage. The bioassay results revealed that the three transgenic rice lines exhibited significantly high resistance against C. suppressalis larvae throughout the rice growing season. According to Cry protein levels in rice tissues, the raw and corrected mortalities of C. suppressalis caused by each Bt rice line were the highest in the seedling and declined through the j ointing stage with an exception for T1 C-19b providing an excellent performance at the maturing stage. By comparison, T1C-19b exhibited more stable and greater resistance to C. suppressalis larvae than T2A-1, being close to Huahui 1. The results suggest crylC is an ideal Bt gene for plant transformation for lepidopteran pest control, and T1C-19b is a promising Bt rice line for commercial use for tolerating lepidopteran rice pests.

关键词： Chilo suppressalis crylAb/Ac cryl C ery2A pest resistance transgenic rice