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Open Journal of Obstetrics and Gynecology 2015年第10期5卷 553-563页

作者： Shui Lam mak Kam On Kou Chung Fan Poon wei ling teresa ma Kwok Yin Leung Department of Obstetrics and Gynaecology Queen Elizabeth Hospital Hong Kong China

Objectives: To determine if the use of high frequency linear transducer (HFLT) in addition to conventional curvilinear transducer (CCT) aids assessment of fetal cardiac and non-cardiac anatomy in the first trimester. Methods: Transabdominal CCT (4 - 8 MHz) followed by HFLT (9 MHz) was used to study prospectively the visualization rate of basic and optional anatomical structures according to international guidelines. McNemar and Chi-square test were used to compare correlated and independent proportions respectively. Postnatal outcomes were traced. Results: Comparing with CCT alone, additional use of HFLT did not improve the completion rate of basic anomaly screen (95.0% vs. 97.0%, p = 0.5) in the 101 women studied, but it improved the visualization rate of some optional structures including lens (57.4% vs. 73.3%), three-vessel view (3 VV) (17.8% vs. 48.5%), left ventricular outflow tract (17.8% vs. 51.5%), kidneys (8.9% vs. 47.5%), and umbilical artery (86.1% vs. 93.1%) (all p maly screen, nor does it achieve a high visualisation rate of different cardiac views in the first trimester.

关键词： Ultrasonography First-Trimester Transducter Fetal Anatomy

Symmetry and monotonicity of positive solutions to Schr?dinger systems with fractional p-Laplacians

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Applied mathematics(A Journal of Chinese Universities) 2022年第1期37卷 52-72页

作者： ma ling-wei ZHANG Zhen-qiu School of mathematical Sciences Tianjin Normal UniversityTianjin 300387China School of mathematical Sciences and LPMC Nankai UniversityTianjin 300071China

In this paper,we first establish narrow region principle and decay at infinity theorems to extend the direct method of moving planes for general fractional p-Laplacian *** virtue of this method,we investigate the qualitative properties of positive solutions for the following Schrodinger system with fractional p-Laplacian{(-△)^(s)_(p)u+au^(p-1)=f(u,v),(-△)^(t)_(p)v+bv(p-1)=g(u,v),where 0main and the nonexistence on the half space for positive solutions to the above system under some suitable conditions on f and g,respectively.

关键词： fractional p-Laplacian Schr?dinger systems direct method of moving planes radial symmetry monotonicity nonexistence

Bioinformatics analysis of structure and function in the MRP gene family and its expression in response to various drugs in Bursaphelenchus xylophilus

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Journal of Forestry Research 2021年第2期32卷 779-787页

作者： Jian Diao Xin Hao wei ma ling ma College of Forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China Heilongjiang University of Chinese Medicine Harbin 150000People’s Republic of China

Genes homologous to members of the MRP gene family in Caenorhabditis elegans are important in drug *** further explore the molecular mechanism of drug resistance in pine wood nematode(Bursaphelenchus xylophilus),we used bioinformatics approaches to analyze genomic data for *** and identified Bx-MRP *** predicted the structure and function of the genes and encoded *** bioinformatics programs to predict and analyze various properties of the predicted proteins,including hydrophobicity,transmembrane regions,phosphorylation sites,and topologically isomeric structures,of these Bx-MRP genes,we determined that they function in transmembrane *** the results of RT-qPCR,the Bx-MRP family members confer significant differential resistance to different drug *** treatment with different concentrations of emamectin benzoate,avermectin and matrine,the expression of each gene increased with increasing drug concentrations,indicating that the family members play a positive role in the regulation of multidrug resistance.

关键词： Bursaphelenchus xylophilus Bx-MRP gene family Gene and protein structure Bioinformatics Multidrug stress

Overexpression of the PdpapERF109 gene enhances resistance of Populus davidiana×*** *** to Fusarium oxysporum infection

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Journal of Forestry Research 2022年第6期33卷 1925-1937页

作者： Jian Diao Mingrui Li Ping Zhang Cheng Zong wei ma ling ma College of Forestry Northeast Forestry UniversityHarbinPeople’s Republic of China College of Wildlife and Protected Area Northeast Forestry UniversityHarbinPeople’s Republic of China College of Medicine Heilongjiang University of Chinese MedicineHarbinPeople’s Republic of China

The key transcription factor gene PdP apE RF109 was cloned from Populus davidiana×*** ***(Pdpap),and after overexpression of P dP ap ERF109 in transformants,the gene functions in the resistance response to Fusarium oxysporum *** with the wild Pdpap,after inoculation with ***,the physiological and biochemical characteristics,including relative fresh weight,peroxidase activity,and the percentage of electrolyte leakage showed that,after overexpression of the PdPapERF109 gene,the transformants grew well and displayed significant resistance to *** *** comparing the reactive oxygen species scavenging capacity of Pdpap plants after pathogen infection,the P dPapERF109-overexpressing plants had significantly better reactive oxygen species scavenging ability than the wild *** analysis of plant morphology and various physiological and biochemical parameters showed that the overexpression of the P dpapERF109 gene significantly improved the resistance of Pdpap plants to *** root ***,increasing the expression of the homologous ERF109 gene can be an effective strategy to increase disease resistance in hybrid poplars.

关键词： ERF Fusarium oxysporumtolerance Gene over-expression Genetic transformation Transcription factor

Synthesis of 5-Substituted-3-[(2’R,4’R)-4’-Hydroxy-2’-hydroxymethyltetrahydrofuran-4’-yl]-1,2,4-oxadiazoles and Their Epimers

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Chemical Research in Chinese Universities 2001年第4期17卷 407-414页

作者： WU wei-dong ma ling-tai ZHANG Li-he National Laboratory of Natural and Biomimetic Drugs School ofPharmaceutical SciencesPeking UniversityBeijing 100083P.R.China

The syntheses of 5-substituted-3-[( 2’ R, 4’ R)-4 ’ -hydroxy-2 ’ -hydroxymethyltetra-hydrofuran-4’ -yl]D-1 ,2, 4-oxadiazoles and their epimers were accomplished with the aid of th construction of 1,2, 4-oxadiazoles by condensation of O-acylated cyanohydrins with hydroxylamine via intramolecular transacylation and subsequent cyclization.

关键词： Nucleoside analogue 1,2,4-Oxadiazole Transacylation

A scaling phenomenon for the cross section of fragment produced in projectile fragmentation reactions

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Science China(Physics,Mechanics & Astronomy) 2019年第9期62卷 60-69页

作者： Yi-Dan Song Hui-ling wei Chun-Wang ma Institute of Particle and Nuclear Physics Henan Normal University

A scaling phenomenon has been found for the cross section of a fragment, which is defined as a "square" cross section(SCS).This phenomenon can unify the cross sections of fragments in projectile fragmentation(PF) reactions. An empirical formula is proposed to calculate SCSfor a fragment with parameters determined by an extensive investigation of measured reactions ranging from Fermi energies to relativistic energies. The scaling phenomenon of SCShas been verified using different techniques,showing that the scaling of SCSgenerally exists in PF reactions. The concept of SCS, which can be assumed as a standard value for a fragment, is shown to accurately predict the cross sections of isotopes in PF reactions with incident energies ranging from tens of A MeV to approximately 1000 A MeV.

关键词： scaling phenomenon cross section prediction intermediate mass fragments projectile fragmentation

Binding energies of near proton-drip line Z = 22-28 isotopes determined from measured isotopic cross section distributions

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Science China(Physics,Mechanics & Astronomy) 2019年第1期62卷 63-68页

作者： Chun-Wang ma Yi-Dan Song Hui-ling wei College of Physics and materials Science Henan Normal University Institute of Particle and Nuclear Physics Henan Normal University

A new method is proposed to determine the binding energy(B)of near proton-drip line isotopes from isotopic cross section *** determine B of Z=22-28 isotopes(with T_z=-2 and-5/2),the lack of cross sections for proton-rich isotopes in the 345A MeV^(78)Kr+~9Be is overcome by predicting the proton-rich isotopes from a newly discovered scaling phenomenon found in the proton-rich isotopes measured in the 140A MeV^(40,48)Ca(^(58,64)Ni)+~9Be *** cross sections for proton-rich isotopes are verified to exponentially depend on the average binding energy per nucleon,based on which B of the Z=22-28 isotopes with T_z=-2 and-5/2 are determined from cross *** determined B of the isotopes are justified from obeying the scaling phenomenon of the difference between the mass of mirror *** cross sections for the Z=22-28 isotopes with T_z=-1 and-3/2,which in potential can be experimentally studied in mass storage ring,are also predicted.

关键词： proton drip line binding energy mirror nuclei scaling phenomenon

Higher Order Fractional Differentiability for the Stationary Stokes System

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Acta mathematica Sinica,English Series 2023年第1期39卷 13-29页

作者： ling wei ma Zhen Qiu ZHANG Qi XIONG School of mathematical Sciences Tianjin Normal UniversityTianjin 300387P.R.China School of mathematical Sciences and LPMC Nankai UniversityTianjin 300071P.R.China School of mathematical Sciences Nankai UniversityTianjin 300071P.R.China

This paper focuses on the higher order fractional differentiability of weak solution pairs to the following nonlinear stationary Stokes system{div A(x-Du)-■π=divF,inΩdivu=0,inΩ.In terms of the difference quotient method,our first result reveals that if F∈B_(p,***)^(β)(Ω,R^(n))for p=2 and 1≤q≤2n/n-2β,then such extra Besov regularity can transfer to the symmetric gradient Du and its pressureπwith no losses under a suitable fractional differentiability assumption on x■A(x,ξ).Furthermore,when the vector field A(x,Du)is simplified to the full gradient■u,we improve the aforementioned Besov regularity for all integrability exponents p and q by establishing a new Campanato-type decay estimates for(■u,π).

关键词： Higher order fractional differentiability Stokes system Besov spaces

Study on water corrosion behavior of ZrSiO_4 materials

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Journal of Advanced Ceramics 2018年第4期7卷 336-342页

作者： ling LIU wei ZHENG Zhuang ma Yanbo LIU School of materials Science and Engineering Beijing Institute of Technology National Key Laboratory of Science and Technology on materials under Shock and Impact

ZrSiO_4 bulk was prepared by pressureless sintering process and ZrSiO_4 coating was deposited on the SiC f/Si C substrate using air plasma method. The microstructures of ZrSiO_4 bulk and ZrSiO_4 coating are both dense. A preliminary study of a water vapor corrosion test for ZrSiO_4 bulk and ZrSiO_4 coating was performed under the conditions of 1.013×105 Pa, 90%H_2O/10%O_2, 1300 ℃, and low gas velocity. Results show that some pores appear on the surface of the ZrSiO_4 bulk. The main crystal phase is ZrO_2 and the weight loss of ZrSiO_4 bulk is only 0.236 mg/cm^2 after corrosion. The ZrSiO_4 coating peels off from the substrate after 109 h. The number and intensity of diffraction peaks of ZrO_2 in the coating increase, and the major crystal phase of the coating is still ZrSiO_4. A porous microstructure accompanied with cracks is observed on the surface of ZrSiO_4 coating after corrosion.

关键词： ZrSiO4 SiCf/SiC substrate environmental barrier coating (EBC) water vapor corrosion behavior

2,3-Dimercaptosuccinic acid self-assembled gold electrode for the simultaneous determination of epinephrine and dopamine

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Chinese Chemical Letters 2009年第2期20卷 221-224页

作者： wei Jun Kang ling Mei Niu Li ma School of Public Health Hebei Medical University Shijiazhuang 050017 China

Simultaneous determination of epinephrine （EP） and dopamine （DA） at 2,3-dimercaptosuccinic acid （DMSA） modified electrode was studied. The oxidation peaks of the mixture of EP and DA appeared at the same potential, but the cathodic peak currents were only linear to the concentration of DA, whereas the anodic peak currents were equal to the sum of individual anodic peak currents of EP and DA. Therefore, a novel electrochemical method for the simultaneous determination of EP and DA at a DMSA modified electrode （DMSA/Au electrode） by cyclic voltammetry was established. The DMSA self-assembled electrode showed good sensitivity, selectivity and stability and could be used to determine DA and EP, simultaneously, in the real application with satisfactory results.

关键词： 2,3-Dimercaptosuccinic acid Simultaneous determination Dopamine Epinephrine