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Differentiation of Four Pairs of Isomers by Comparing Their Relative Abundances of Fragment Ions

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Chemical Research in Chinese Universities 2010年第1期26卷 27-32页

作者： SUN Ming-qian LU Jian-qiu zhang Hong-gui zhang qun-shu XIAO Nan Rui-yun School of Chinese Materia Medica Beijing University of Chinese Medicine Beijing 100102 P R. China Developing Center of Science and Technique Beijing University of Chinese Medicine BeoTng 100029 P. R. China Pharmaceutical University of Shenyang Shenyang 110016 P R. China

Based on the LC-ESI/MSn technique, the four pairs of isomers of psoralen and isopsoralen, imperatorin and isoimperatorin, neohesperidin and hesperidin, naringin and narirutin were distinguished mainly by comparison of the relative abundances of their major fragment ions. Because of the effect of the hydrogen on the C8 of psoralen, the intensity of the fragment ion formed by the loss of CO2 was relatively increased. By comparing the abundance of the product ions formed by the loss of CO and 2CO, the isomers of psoralen and isopsoralen could be distinguished. This method can also be used to distinguish the isomers of imperatorin and isoimperatorin. Because of the different con- nected position between glucose and rhamnose, in the mass spectrum of neohesperidin, the relative abundances of ions at m/z 489 and 343 generated by the ring-cross cleavage of glycan were more than 10%, while in the mass spec- trum of hesperidin, they were all less than 1%. This approach can also be used to distinguish the isomers ofnaringin and narirutin. Although the fragmentation pathways were similar, according to the tiny difference of structure, the change of relative intensity of main fragment ions could be observed and it could be used to distinguish some isomers more accurately and quickly.

关键词： LC-MSn Relative abundance Isomer Product ion Generation opportunity

Regulation of developmental and environmental signaling by interaction between microtubules and membranes in plant cells

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Protein & Cell 2016年第2期7卷 81-88页

作者： qun zhang Wenhua zhang College of Life Sciences State Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing AgriculturalUniversity Nanjing 210095 China

Cell division and expansion require the ordered arrangement of microtubules, which are subject to spatial and temporal modifications by developmental and environmental factors. Understanding how signals translate to changes in cortical microtubule organization is of fundamental importance. A defining feature of the cortical microtubule array is its association with the plasma membrane; modules of the plasma membrane are thought to play important roles in the mediation of microtubule organization. In this review, we highlight advances in research on the regulation of cortical microtubule organization by membrane-associated and membrane-tethered proteins and lipids in response to phytohormones and stress. The transmembrane kinase receptor Rho-like guanosine triphosphatase, phospholipase D, phosphatidic acid, and phosphoinositides are discussed with a focus on their roles in microtubule organization.

关键词： abiotic stresses cortical microtubule,lipids plasma membrane

Lie Symmetries and Non-Noether Conserved Quantities of Nonholonomic Systems

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Communications in Theoretical Physics 2004年第3X期42卷 321-324页

作者： zhangHong-Bin CHENLi-qun shu-Long ShanghaiInstituteofAppliedMathematicsandMechanics ShanghaiUniversityShanghai200072China DepartmentofPhysics ChaohuTeacher'sCollegeChaohu238000China

A new conservation theorem of the nonholonomic systems is studied. The conserved quantity is onlyconstructed in terms of a general Lie group of transformation vector of the dynamical equations. Firstly, we establish thedynamical equations of the nonholonomic systems and the determining equations of Lie symmetry. Next, the theore mof non-Noether conserved quantity is deduced. Finally, we give an example to illustrate the application of the result.

关键词：李对称非Noether守恒量不完整系统守恒定律李群矢量转换

Existence and Regularity of Solution to the Generalized Tricomi Equation with a Singular Initial Datum at a Point

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Acta Mathematica Sinica,English Series 2012年第6期28卷 1135-1154页

作者： Kang qun zhang Department of Mathematics&IMS Nanjing University

In this paper, we study the existence and regularity of a solution to the initial datum problem of a semilinear generalized Tricomi equation in mixed-type initial datum on the degenerate plane is smooth away from the origin, domain. We suppose that an and has a conormal singularity at this point, then we show that in some mixed-type domain, the solution exists and is conormal with respect to the characteristic conic surface which is issued from the origin and has a cusp singularity.

关键词： Generalized Tricomi equation confluent hypergeometric function existence conormalregularity cusp singularity

A Note on Initial Value Problem for the Generalized Tricomi Equation in a Mixed-type Domain

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Acta Mathematica Sinica,English Series 2013年第8期29卷 1581-1596页

作者： Kang qun zhang Department of Mathematics and Physics Nanjing Institute of Technology

In this paper, we study the well-posedness of initial value problem for n-dimensional gener-alized Tricomi equation in the mixed-type domain {（t,x）：t∈[1,＋∞）,x∈Rn} with the initial data given on the line t=1 in Hadamard＇s sense. By taking partial Fourier transformation, we obtain the explicit expression of the solution in terms of two integral operators and further establish the global estimate of such a solution for a class of initial data and source term. Finally, we establish the global solution in time direction for a semilinear problem used the estimate.

关键词： Generalized Tricomi equation semilinear initial value problem mixed-type domain

Existence of a-Cores for Games Without Compact Assumptions

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Journal of the Operations Research Society of China 2024年第2期12卷 520-527页

作者： Hai-qun zhang School of International Economics and Trade Shanghai Lixin University of Accounting and Fin Shanghai201209China

Following the representation of Kajii(J Econ Theory 56:194-205,1992),we provide some existence theorems ofα-cores for games without ordered preferences and compact *** applications,we obtain some existence results of... 详细信息

关键词： α-Core Existence Preference Noncompactness

Regression Analysis of Doubly Censored Data with a Cured Subgroup under a Class of Promotion Time Cure Models

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Acta Mathematica Sinica,English Series 2021年第6期37卷 835-853页

作者： Min CAI Li qun XIAO shu Wei LI School of Economics and Statistics Guangzhou UniversityGuangzhou 510006P.R.China

In some situations,the failure time of interest is defined as the gap time between two related events and the observations on both event times can suffer either right or interval *** data are usually referred to as doubly censored data and frequently encountered in many clinical and observational ***,there may also exist a cured subgroup in the whole population,which means that not every individual under study will experience the failure time of interest *** this paper,we consider regression analysis of doubly censored data with a cured subgroup under a wide class of flexible transformation cure ***,we consider marginal likelihood estimation and develop a two-step approach by combining the multiple imputation and a new expectation-maximization(EM)algorithm for its *** resulting estimators are shown to be consistent and asymptotically *** finite sample performance of the proposed method is investigated through simulation *** proposed method is also applied to a real dataset arising from an AIDS cohort study for illustration.

关键词： Doubly censored data marginal likelihood EM algorithm multiple imputation transformation cure models

Real-time Quantitative RT-PCR for CT9 Level in Human Cancer

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Chemical Research in Chinese Universities 2006年第2期22卷 185-188页

作者： JIN Xiang-qun zhang Jing-min XU Hui ZHOU Yan WANG Guang-shu ZHAO Yan-qiu zhang Han-qi College of Chemistry Jilin University Changchun 130012 P. R. China College of Phamercy Jilin University Changchun 130021 P. R. China College of Nurse Jilin University Changchun 130021 P. R. China No. 2 Affiliated Hospital Jilin University Changchun 130021 P. R. China

CT9 is a recently cloned cancer-testis antigen, which is a member of the bromodomain and extraterminal family. Each member of this protein family contains two N-terminal bromodomain motifs. We investigated the distribution of CT9 in different tissues and the possibility for it to be used as a potential therapeutic target in cancer treament. By using the real-time RT-PCR method and 18SrRNA as an internal standard, we analyzed the CT9 expression in several normal human tissues and in the tissues of patients suffering from cancer. The result of this study shows that the highest level of mRNA is only present in testis tissue because the CT9 expression has not been detected in other normal tissues. In 6 of 10 cases of gastric adenocarcinoma, in 3 of 10 cases of esophageal squamous cell carcinoma, in 2 of 9 cases of endometrial carcinoma and only in 1 of 12 cases of brain cancer, the low level expression of CT9 was detected. In none of the 12 cases of cervical squamous cell carcinoma, the expression of CT9 was detected. Since the high level expression of CT9 is only found in the normal testis tissue, but the low expression in cancer tissues, for example tissues of cervical squamous cell carcinoma, brain cancer, endometfial adenocarcinoma, esophageal squamous cell carcinoma, we conclude that CT9 cannot be used as a cancer therapeutic target molecule for cervical squamous cell carcinoma, brain cancer, endometrial adenocarcinoma, esophageal squamous cell carcinoma.

关键词： CT9 Cancer-testis antigen Real-time RT-PCR

Activation cross sections for reactions induced by 14 MeV neutrons on natural copper

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Nuclear Science and Techniques 2018年第10期29卷 254-260页

作者： Jing-Jie Ma Feng-qun Zhou Xiao-Jun Sun Xiao-Peng zhang shu-Qing Yuan School of Electrical and Mechanical Engineering Pingdingshan UniversityPingdingshan 467000China Henan Quality Polytechnic Pingdingshan 467000China

The cross sections for the^(63)Cu(n,a)^(60(m+g))Co,^(65)Cu(n,2 n)^(64)Cu, and ^(65)Cu(n,p)^(65)Ni reactions have been studied in the neutron energy range of 13.5–14.8 MeV using the activation technique. The neutron beams were produced via the^3 H(d,n)~4 He reaction. The neutron energies of different directions in the measurements were determined beforehand by the method of cross section ratios for the^(90)Zr(n,2 n)^(89 m+g)Zr and ^(93)Nb(n,2 n)^(92 m)Nb reactions. The results in the present work were discussed and compared with measurement results found in the literatures.

关键词： Copper Activation Neutron Cross section Nuclear reaction