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Agricultural Sciences in China 2010年第6期9卷 903-910页

作者： WU Shao-qiang LIN xiang-mei ZHU Xing-quan Institute of Animal and Plant Quarantine Chinese Academy of Inspection and Quarantine Beijing 100029 P.R.China State Key Laboratory of Veterinary Etiological Biology Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences Lanzhou 730046 P.R. China

In order to provide further evidence to prove that Ascaris suum Goeze,1782 and Ascaris lumbricoides Linnaeus,1758 are really different species in taxonomy,and to identity *** larval migrans-related genes for diagnosis and prevention use,*** genes that were differentialy expressed from the same gender of *** were enriched by subtracting the same expressed genes using suppression subtractive hybridization （SSH） *** of the selectively enriched cDNA was verified by Southern blot *** female *** specific cDNA library was then constructed and *** local alignment search tool （BLAST） analysis of female *** specific cDNA identified 6 specific ESTs with tentative functions related to larva *** study provided further evidence for differentiating *** from *** for the detailed information and application of the 6 ESTs are worth being done in the future studies.

关键词： Ascaris suum Ascaris lumbricoides nematode suppression subtractive hybridization EST larva migrans

Morphology and features of Cambrian oncoids and responses to palaeogeography of the North China Platform

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Journal of Palaeogeography 2020年第2期9卷 150-167页

作者： En-Zhao Xiao Ming-xiang mei Shu Jiang Tehseen Zafar School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education and Faculty of Earth Resources China University of Geosciences(Wuhan)Wuhan 430074China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081China Institute of Geology University of the PunjabLahore 54590Pakistan

The Cambrian strata in the North China Platform are fully exposed. A wide variety of carbonate oncoids with different shapes occur in the Xuzhuang and Zhangxia formations(Miaolingian Series) from six Cambrian sections in the study area. A comprehensive study involving outcrop description, microscopic observation, scanning electron microscopy(SEM), energy dispersive X-ray spectroscopy(EDX), X-ray diffraction(XRD), and carbon and oxygen isotope analysis is conducted to determine the facies, morphology, internal structure, and geochemical properties of the oncoids. The oncoids are divided into six types based on their morphology and internal *** and ultrastructural observations reveal typical microbial fossils(Girvanella) and microbially-related sediments(framboidal pyrite), indicating the biogenicity of the oncoids. Additionally, the XRD and carbon and oxygen isotope analysis results suggest that the formational environments of these oncoids are different due to terrestrial influences. Statistical data on the oncoids from the six sections show that there are obvious differences in the types of oncoids and the proportions of different varieties in each section. The spatial differences in the oncoid morphologies are associated with different palaeogeographic settings. The rough oncoid growth patterns developed in nearshore environments were influenced by terrigenous debris and steep terrain, whereas the delicate oncoid growth patterns developed in offshore environments were less affected by terrestrial factors and were featured by more stable depositional processes related to microbial mats.

关键词： Morphological classification Microbial m at Girvonello Carbon and oxygen isotopes Miaolingian series North China

DFT Study on the Structure and Racemization Mechanism of 1,1 ＇- Bina phthalene-8,8 ＇-diol

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Chinese Journal of Chemical Physics 2008年第4期21卷 367-375页

作者： Liang-guo Da Tong-tong Lu mei xiang Tian-jing He Dong-ming Chen Department of Chemical Physics University of Science and Technology of China Hefei 230025 China Department of Chemical Biology Huainan Normal University Huainan 232001 China

Density functional theory （DFT） was applied to study the ground state geometries and isomerization processes of 1,1＇-binaphthalene-8,8＇-diol. Three isomers, denoted as ISO1, ISO2, and ISO3, were found, distinguished by different orientations of the OH groups, and each OH-orientational isomer has R- and S-enantiomer. The conformational stabilities of these isomers were investigated by tracking the energy change with respect to the ring-to-ring torsion. The inter-conversions between the three OH-orientational S-isomers were found to have quite low barriers owing to the nearly free rotation of OH groups around the O-C single bonds. The S-R enantiomerization of ISO1 and ISO2 can take place through the ring-ring torsion around the C1-C1/ single bond, either in the anti-rotation manner or in the syn-rotation manner. The barriers of the anti routes are lower than those of the corresponding syn routes by 87.95 and 75.04 kJ/mol. For the S-R enantiomerization of ISO3, only the anti route was found. The barriers for the anti route enantiomerizations of ISO1, ISO2, and ISO3 are 119.61, 120.43, and 121.59 kJ/mol, respectively. A parallel reaction mechanism via three anti enantiomerization routes was proposed for the racemization of 1,1＇-binaphthalene-8,8＇-diol.

关键词： Density functional theory (DFT) 1 1'-Binaphthalene-8 8'-diol Racemization

类氦C离子诱发不同金属厚靶原子的K-X射线

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物理学报 2024年第4期73卷 136-143页

作者：梅策香张小安周贤明梁昌慧曾利霞张艳宁杜树斌郭义盼杨治虎咸阳师范学院离子束与光物理实验室咸阳712000 中国原子能科学研究院核物理研究所北京102413 中国科学院近代物理研究所兰州730000

利用中国原子能科学研究院HI-13MV串列加速器上提供的动能为15—55 MeV的类氦C离子分别轰击Fe,Ni,Nb和Mo金属厚靶,采用HpGe探测器测量了K-X射线,获得了相应的K-X射线的发射截面.本文中由于各个靶原子外壳层电离度的不同,类氦C离子与Fe,N... 详细信息

利用中国原子能科学研究院HI-13MV串列加速器上提供的动能为15—55 MeV的类氦C离子分别轰击Fe,Ni,Nb和Mo金属厚靶,采用HpGe探测器测量了K-X射线,获得了相应的K-X射线的发射截面.本文中由于各个靶原子外壳层电离度的不同,类氦C离子与Fe,Ni靶原子相互作用发射的K_(β)与K_(α)X射线的分支强度比随入射离子动能增加而减小,而Nb,Mo靶原子发射的K-X射线分支强度比变化不明显.利用厚靶截面公式计算了靶原子K-X射线的发射截面,并与不同的理论模型及质子的结果进行了对比.结果表明随类氦C离子动能的增大,Fe,Ni靶原子发射的K_(β)与K_(α)X射线的总产生截面与考虑多电离的两体碰撞近似修正模型最为符合Nb,Mo靶原子发射的K_(β)与K_(α)X射线的总产生截面与平面波恩近似模型的理论值最为接近.质子与单核子C离子能量相同时,质子比类氦C离子激发不同靶的K-X射线产生截面约小3个数量级.

关键词： X射线粒子束截面两体碰撞近似平面波恩近似

High efficiency hydrogen purification through P2C3 membrane:A theoretical study

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Chinese Physics B 2019年第12期28卷 389-392页

作者： Zhao-Qin Chu Xiao Gu xiang-mei Duan Department of Physics Ningbo UniversityNingbo 315211China Laboratory of Clean Energy Storage and Conversion Ningbo UniversityNingbo 315211China

It is critical to design an effective two-dimensional membrane for hydrogen purification from the mixed gas, due to its wide range of scientific and industrial applications. In this work, we investigate the hydrogen separation performance of P2C3 membranes by density functional theory and molecular dynamics simulations. The results show that the energy barrier of the H2 molecule through the P2C3 film is only 0.18 e V, while the energy barriers of the CO, N2, CO2, and CH4 molecules are 0.77 eV, 0.87 eV, 0.52 eV, and 1.75 eV, respectively. In addition, the P2C3 film has high H2 selectivity toward other gas molecules and high H2 permeability at room temperature. Under 6% tensile strain, 82% hydrogen molecules pass through the film with a H2 permeance of 2.22 × 107 gas permeance unit(GPU), while other molecules cannot across the membrane at all. Therefore, the P2C3 membrane is an excellent material for hydrogen purification.

关键词： two-dimensional membrane hydrogen separation first-principles

Bifurcation of Periodic Orbits and Chaos in Duffing Equation

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Acta Mathematicae Applicatae Sinica 2006年第3期22卷 495-508页

作者： mei-xiang Cai Jian-ping Yang Department of Mathcmatics Hunan Normal University Changsha 410081 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 Chian and Graduate School of the Chinese Academy of Sciences Beijing 100039

Duffing equation with fifth nonlinear-restoring force, one external forcing and a phase shift is investigated, The conditions of existences for primary resonance, second-order, third-order subharmonics, morder subharmonics and chaos are given by using second-averaging method, Melnikov methods and bifurcation theory. Numerical simulations including bifurcation diagrams, bifurcation surfaces, phase portraits, not only show the consistence with the theoretical analysis, but also exhibit the new dynamical behaviors. We show the onset of chaos, chaos suddenly disappearing to period orbit, one-band and double-band chaos, period-doubling bifurcations from period 1, 2, and 3 orbits, period-windows （period-2, 3 and 5） in chaotic regions.

关键词： Duffing equation Melnikov's method second-order averaging method chaos

Positive psychological intervention for anxiety, depression and coping in subjects addicted to online games

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World Journal of Clinical Cases 2021年第14期9卷 3287-3293页

作者： Xiu-Jun Gao Ji-Jun Sun mei xiang Department of Psychiatry Hangzhou Seventh People’s HospitalHangzhou 310013Zhejiang ProvinceChina Department of Elderly Psychiatry Hangzhou Seventh People’s HospitalHangzhou 310013Zhejiang ProvinceChina

BACKGROUND Addiction to online games is not *** patients usually refuse to take medications and present with affective symptoms such as anxiety,depression and negative coping *** intervention based on positive psychology is a promising treatment for such *** To evaluate the effect of positive psychological intervention on anxiety,depression and coping in people addicted to online *** This self-controlled study included 89 people addicted to online games,who received treatment at Hangzhou Seventh People’s Hospital,Hangzhou,China in *** Hamilton Anxiety Scale,Hamilton Depression Scale and Trait Coping Style Questionnaire were administered to evaluate the anxiety,depression and coping style among these *** intervention based on positive psychology was provided for 6 wk followed by another *** results were compared against those from the previous *** After 6 wk of psychological intervention,89 people achieved a significant improvement in the Hamilton Anxiety Scale and Hamilton Depression Scale-24 *** score for positive coping style in Trait Coping Style Questionnaire was significantly improved,while that of the negative coping style decreased significantly(P<0.05).CONCLUSION Psychological intervention based on positive psychology alleviated affective symptoms,such as anxiety and depression,in subjects addicted to online *** intervention corrected negative coping style,thereby improving mental health.

关键词： Online game addiction Positive psychology Anxiety Depression Coping style Psychological intervention

Weak Noether Symmetry and non-Noether Conserved Quantities for General Holonomic Systems

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Communications in Theoretical Physics 2008年第10期50卷 844-846页

作者： XIE Jia-Fang mei Feng-xiang GANG Tie-Qiang Department of Mechanics Beijing Institute of Technology Beijing 100081 China

A new kind of weak Noether symmetry for a general holonomic system is defined in such a way that themethods to construct Hojman conserved quantity and new-type conserved quantity are *** turns out that weintroduce a n... 详细信息

关键词： weak Noether symmetry non-Noether conserved quantity general holonomic system

Weakly Noether Symmetry for Nonholonomic Systems of Chetaev's Type

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Communications in Theoretical Physics 2008年第6期49卷 1413-1416页

作者： mei Feng-xiang XIE Jia-Fang GANG Tie-Qiang Department of Mechanics Beijing Institute of Technology Beijing 100081 China

In the paper [J. of Beijing Institute of Technology 26 （2006） 285] the authors provided the definition of weakly Noether symmetry. We now discuss the weakly Noether symmetry for non-holonomic system of Chetaev＇s type, and present expressions of three kinds of conserved quantities by weakly Noether symmetry. Finally, the application of this new result is shown by a practical example.

关键词： weakly Noether symmetry conserved quantity nonholonomic systems of Chetaev's type

Tea consumption and risk of stroke:a dose-response meta-analysis of prospective studies

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第8期13卷 652-662页

作者： Li SHEN Liu-guang SONG Hong MA Chun-na JIN Jian-an WANG mei-xiang xiang Department of Cardiology the Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009China Cardiovascular Key Lab of Zhejiang Province the Second A3filiated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009China

Objective:To determine the association between tea consumption and the risk of stroke. Methods:We searched the PubMed database from January 1966 to March 2012 and reviewed reference lists of retrieved articles to identify relevant studies. Studies were included if they reported relative risks (RRs) and corresponding 95% confidence intervals (CIs) of stroke with respect to three or more categories of tea consumption. A random-effects model was used to combine the study-specific risk estimates. Results:Fourteen studies, consisting of 513 804 participants with a median follow-up of 11.5 years, were included in this meta-analysis. We observed a modest but statistically significant inverse association between tea consumption and risk of stroke. An increase of three cups/d in tea consumption was associated with a 13% decreased risk of stroke (RR 0.87; 95% CI, 0.81-0.94). The decreased risk of stroke with tea consumption was consistent among most subgroups. Based on the three studies that provided results for stroke subtypes, tea consumption was also inversely associated with the risk of ischemic stroke (RR 0.76; 95% CI, 0.69-0.84), but not cerebral hemorrhage (RR 0.96; 95% CI, 0.82-1.11) or subarachnoid hemorrhage (RR 0.81; 95% CI, 0.57-1.16). Conclusions:Tea consumption is associated with a decreased risk of stroke, particularly ischemic stroke. More well-designed, rigorously conducted studies are needed in order to make confident conclusions about the association between tea consumption and stroke subtypes.

关键词： Tea Stroke Prospective studies Dose-response meta-analysis