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The Relationship between the Nonexistence of Generalized Bent Functions and Diophantine Equations

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Acta Mathematica Sinica,English Series 2011年第6期27卷 1173-1186页

作者： Feng mei liu Qin YUE National Key Laboratory on Information Assurance Technology Sub-box 21 Box 7227 Beijing 100072 P. R. China Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

Two new results on the nonexistence of generalized bent functions are presented by using properties of the decomposition law of primes in cyclotomic fields and properties of solutions of some Diophantine equations, an... 详细信息

关键词： Generalized bent function integral basis Diophantine equation

Extremal Graphs with Respect to Matching Energy for Random Six-membered Ring Spiro Chains

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Acta Mathematicae Applicatae Sinica 2019年第2期35卷 319-326页

作者： Hua-mei CHEN Yan liu School of Mathematical Sciences South China Normal University

Gutman and Wagner(in the matching energy of a graph, Disc. Appl. Math., 2012) defined the matching energy of a graph and pointed out that its chemical applications go back to the 1970 s. Now the research on matching energy mainly focuses on graphs with pendent vertices and only a few papers reported the progress on matching energy of graphs without pendent vertices. For a random six-membered ring spiro chain, the number of k-matchings and the matching energy are random variables. In this paper, we determine the extremal graphs with respect to the matching energy for random six-membered ring spiro chains which have no pendent vertices.

关键词： matching energy random six-membered ring spiro chains

Panconnectivity for Interconnection Networks with Faulty Elements

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Acta Mathematica Sinica,English Series 2010年第4期26卷 647-652页

作者： mei LU Hui Qing liu Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China School of Mathematics and Computer Science Hubei University Wuhan 430062 P. R. China

Let Go and G1 be two graphs with the same vertices. The new graph G（G0, G1; M） is a graph with the vertex set V（0o） ∪）V（G1） and the edge set E（Go） UE（G1） UM, where M is an arbitrary perfect matching between the vertices of Go and G1, i.e., a set of cross edges with one endvertex in Go and the other endvertex in G1. In this paper, we will show that if Go and G1 are f-fault q-panconnected, then for any f 〉 2, G（G0, G1; M） is （f ＋ 1）-fault （q ＋ 2）-panconnected.

关键词： fault vertex fault edge fault panconnected interconnection networks

Eigenvalues and Diameter

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Acta Mathematica Sinica,English Series 2011年第6期27卷 1107-1114页

作者： Hui Qing liu mei LU School of Mathematics and Computer Science Hubei University Wuhan 430062 P. R. China Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China

Let G be a connected graph of order n. The diameter of a graph is the maximum distance between any two vertices of G. In this paper, we will give some bounds on the diameter of G in terms of eigenvalues of adjacency m... 详细信息

关键词： Graph Laplacian matrix adjacency matrix diameter

Evaluation of right ventricular volume and systolic function in normal fetuses using intelligent spatiotemporal image correlation

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World Journal of Clinical Cases 2019年第15期7卷 2003-2012页

作者： Jia-Xing Sun ai-Lu Cai Li-mei Xie Ultrasound Department Shengjing Hospital of China Medical UniversityShenyang 110004Liaoning ProvinceChina Ultrasound Department Roicare Hospital and ClinicsShenyang 110004Liaoning ProvinceChina

BACKGROUND Heart defects are the most common congenital malformations in *** cardiac structure and function abnormalities lead to changes in ventricular *** ventricular volume is an important index for evaluating fetal cardiovascular development,an effective and reliable method for measuring fetal ventricular volume and cardiac function is necessary for accurate ultrasonic diagnosis and effective clinical *** new intelligent spatiotemporal image correlation(iSTIC)technology acquires high-resolution volumetric *** this study,the iSTIC technique was used to measure right ventricular volume and to evaluate right ventricular systolic function to provide a more accurate and convenient evaluation of fetal heart *** To investigate the value of iSTIC in evaluating right ventricular volume and systolic function in normal *** Between October 2014 and September 2015,a total of 123 pregnant women received prenatal ultrasound examinations in our *** technology was used to acquire the entire fetal cardiac volume with off-line analysis using QLAB *** systolic and diastolic phases were defined by opening of the atrioventricular valve and the subsequent closure of the atrioventricular *** volumetric data of the two phases were measured by manual tracking and summation of multiple slices and recording of the right ventricular end-systolic volume and the right ventricular end-diastolic *** data were used to calculate the right stroke volume,the right cardiac output,and the right ejection *** correlations of changes between the above-mentioned indices and gestational age were *** right ventricular volumes of 30 randomly selected cases were measured twice by the same sonographer,and the intraobserver agreement measurements were *** Among the 123 normal fetuses,the mean right ventricular end-diastolic volume increased from 0.99±0.34 mL at 22 wk gestation to 3.69±0.36

关键词： Ultrasonography Fetus Intelligent spatiotemporal image correlation Right ventricular volume Cardiac function

Large Deviation for Supercritical Branching Processes with Immigration

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Acta Mathematica Sinica,English Series 2016年第8期32卷 893-900页

作者： Jing Ning liu mei ZHANG School of Mathematical Sciences Laboratory of Mathematics and Complex SystemsBeijing Normal University

In this paper, we study the large deviation for a supercritical branching process with immigration controlled by a sequence of non-negative integer-valued independently identical distributed random variables, improving the previous results for non immigration processes. We rely heavily on the detail description and limit property of the generating function of immigration processes.

关键词： Supercritical branching processes large deviation immigration

Aromatic Polyimides with Tertbutyl-substituted and Pendent Naphthalene Units:Synthesis and Soluble,Transparent Properties

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Chinese Journal of Polymer Science 2015年第8期33卷 1074-1085页

作者： Chan-juan liu mei mei Xiang-lin Pei 黄孝华 Chun Wei Key Laboratory of New Processing Technology for Nonferrous Metal & Materials Ministry of Educationand School of Material Science and EngineeringGuilin University of Technology Ministry of Education Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical ScienceGuangxi Normal University

A novel non-coplanar aromatic diamine monomer, 3,3＇-ditertbutyl-4,4＇-diaminodiphenyl-4＂-naphthylmethane （TAPN） was synthesized by a condensation reaction of 2-tertbutylaniline and 1-naphthaldehyde under catalyst hydrochloric acid. The structure of the monomer was confirmed by FTIR, NMR, elementary analysis and mass spectrometry. A series of aromatic polyimides （PIs） were synthesized via conventional one-step polycondensation from TAPN and various commercial aromatic dianhydrides. All of the PIs exhibit excellent solubility in common organic solvents, even in low boiling point solvents such as chloroform （CHC13）, tetrahydrofuran （THF） and acetone. The PIs present outstanding thermal stability with the glass transition temperature （Tg） ranged from 299 ℃ to 350 ℃, and the temperature at 10% weight loss ranged from 490 ℃ to 504 ℃, and high optical transparency with the cutoff wavelengths of 306-356 nm. Moreover, the flexible and tough PI films have prominent mechanical properties with tensile strengths in the range of 77.6-90.5 MPa, tensile modulus in the range of 1.8-2.4 GPa and elongation at break in the range of 6.3%-9.5%, as well as lower dielectric constant （2.89-3.12 at 1 MHz） and lower moisture absorption （0.35%-0.66%）.

关键词： Polyimides Solubility Dielectric constant Tertbutyl Naphthyl.

广州市食源性金黄色葡萄球菌肠毒素及耐药分析

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实用预防医学 2018年第4期25卷 398-400页

作者：张健陈惠玲邓志爱罗健梅刘巧谊吴新伟白志军广州市疾病预防控制中心广东广州510440

目的了解广州地区食品和食物中毒样品中金黄色葡萄球菌产肠毒素和耐药性情况。方法按食品安全国家标准和相关文献对2010-2016年广州市疾病预防控制中心微生物实验室从食品和食物中毒样品中分离并保存的118株金黄色葡萄球菌进行了肠毒素... 详细信息

目的了解广州地区食品和食物中毒样品中金黄色葡萄球菌产肠毒素和耐药性情况。方法按食品安全国家标准和相关文献对2010-2016年广州市疾病预防控制中心微生物实验室从食品和食物中毒样品中分离并保存的118株金黄色葡萄球菌进行了肠毒素和药敏试验。结果 118株金黄色葡萄球菌有70株产肠毒素,产毒率为59.32%,快餐类食品和食物中毒样品的产毒率偏高。以荧光PCR方法对70株肠毒素阳性的菌株进行肠毒素A-E分型,其中SEA检出率为29.20%、SEB 17.70%、SEC 11.50%、SED 15.93%、SEE 25.67%;携带两种或以上毒力基因的产毒菌株占41.42%。在受检的菌株中,有104株菌不同程度的对一种或多种的抗生素有抗性,占88.14%;青霉素G耐药率高达71.19%;检出耐甲氧西林金黄色葡萄球菌(MRSA)5株,占4.24%,mec A耐药基因检测阳性。结论广州市食源性金黄色葡萄球菌中产肠毒素菌株较多,且存在耐药株,甚至MRSA,应加强对广州市食品安全风险的监管。

关键词：金黄色葡萄球菌肠毒素耐药性食品安全

Cyproheptadine Regulates Pyramidal Neuron Excitability in Mouse Medial Prefrontal Cortex

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Neuroscience Bulletin 2018年第5期34卷 759-768页

作者： Yan-Lin He Kai Wang Qian-Ru Zhao Yan-ai mei Institutes of Brain Science State Key Laboratory of Medical Neurobiology and School of Life Sciences Fudan University

Cyproheptadine （CPH）, a first-generation anti- histamine, enhances the delayed rectifier outward K＋ current （IK） in mouse cortical neurons through a sigma-1 receptor-mediated protein kinase A pathway. In this study, we aimed to determine the effects of CPH on neuronal excitability in current-clamped pyramidal neurons in mouse medial prefrontal cortex slices. CPH （10 μmol/L） significantly reduced the current density required to generate action potentials （APs） and increased the instan- taneous frequency evoked by a depolarizing current. CPH also depolarized the resting membrane potential （RMP）, decreased the delay time to elicit an AP, and reduced the spike threshold potential. This effect of CPH was mim- icked by a sigma-1 receptor agonist and eliminated by an antagonist. Application of tetraethylammonium （TEA） to block IK channels hyperpolarized the RMP and reduced the instantaneous frequency of APs. TEA eliminated the effects of CPH on AP frequency and delay time, but had no effect on spike threshold or RMP. The current-voltage relationship showed that CPH increased the membrane depolarization in response to positive current pulses and hyperpolarization in response to negative current pulses, suggesting that other types of membrane ion channels might also be affected by CPH. These results suggest that CPH increases the excitability of medial prefrontal cortex neurons by regulating TEA-sensitive IK channels as well as other TEA-insensitive K＋ channels, probably ID and inward-rectifier Kir channels. This effect of CPH may explain its apparent clinical efficacy as an antidepressant and antipsychotic.

关键词： Cyproheptadine Neuronal excitability Te-traethylammonium-sensitive Ik cortical neurons Sigma-1 receptor