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Application of the first internal transcribed spacer(ITS-1)of ribosomal DNA as a molecular marker to population analysis in farrer's scallop Chlamys farreri

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Acta Oceanologica Sinica 2007年第1期26卷 93-100页

作者： yu Ziniu WEI Xiaohua KONG Xiaoyu yu shanshan Laboratory of Applied Marine Biology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China . Key Laboratory of Mariculture of Ministry of Education Ocean University of China Qingdao 266003 China

Sequence variation of the first internal transcribed spacer of ribosomal DNA （ ITS - 1 ） was examined and its application to the study of genetic variation was explored in four populations of farter＇ s scallop Chlamys farreri. ITS - 1 fragments, with a length of about 300 bp,of 78 individuals collected from Dalian, Qingdao, Yantai in China and Korea respectively were amplified via PCR, cloned and sequenced. Intra-genomic variation was examined by sequencing several clones of single individuals. Alignment and polymorphism analysis detected 44 haplotypes and 50 polymorphic sites which consist of 30 substitutions and 20 indels, indicating a high level of polymorphisms. Sequence analysis also showed a very low level of intra-individual variation. All these features validated the feasibility of application of ITS - 1 fragment to population analysis. Polymorphism analysis showed that the Korea sample has the richest genetic variation, followed by Yantai and Qingdao samples. AMOVA （analysis of molecular variance） showed that the majority （96.26%） of genetic variation was distributed within populations and 3.74% resulted from among populations, but with P 〈 0.05 （ = 0.042）, indicating that the populations in this study have significant divergence. This output was basically concordant with the result arising from RAPD data and different from that from mitochondrial 16S rDNA sequence data. Discussion on this inconsistency was made accordingly.

关键词： Chlamys farreri farrer' s scallop internal transcribed spacer ( ITS - 1 ) DNA sequence genetic variation

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One enantiomeric fluorescent sensor pair to discriminate four stereoisomers of threonines

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Science China Chemistry 2013年第3期56卷 301-308页

作者： yu shanshan PU Lin Department of Chemistry University of VirginiaCharlottesvilleVirginia 22904-4319

The BINOL-amino alcohol enantiomeric pair(S)-1 and(R)-1 are discovered to conduct both enantioselective and diastereoselective fluorescent discrimination of the four stereoisomers of threonine *** study utilizes different fluorescence responses of one sensor at two emission wavelengths toward the stereoisomeric substrates which expands the capability of the sensor in chiral *** addition,the sensor pair also allows visual recognition of the N-protected L-allo-threonine and D-allo-threonine by enantioselective precipitation.

关键词： fluorescent sensor enantioselective diastereoselective amino acid threonine BINOL

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Social-Aware Based Secure Relay Selection in Relay-Assisted D2D Communications

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Computers, Materials & Continua 2019年第2期58卷 505-516页

作者： shanshan yu Ju Liu Xiaoqing Zhang Shangbin Wu Shandong University Qingdao266237China. Samsung R&D Institute UK Staines-upon-ThamesTW184QEUK

Relay-assisted transmission could effectively enhance the performance of Device-to-Device(D2D)communications when D2D user equipments(UEs)are too far away from each other or the quality of D2D channel is not good enough for direct ***,security is one of the major concerns for proximity *** secure relay selection problem for D2D communications underlaying cellular network is studied in this ***,we define a relay selection area and derive the closed-form of outage probability in D2D links using a Poisson Point Process(PPP)***,in the defined relay selection area,we propose a secure relay selection scheme for the relay-assisted D2D communication system by exploiting the social relation as a security *** results show that the scheme based on social relation can greatly improve the security performance of relay-assisted D2D communications.

关键词： Device-to-device social-aware security poisson point process

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Novel Annulus-shaped Flexure Pivot in Rotation Application and Dimensionless Design

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 800-809页

作者： BI Shusheng ZHAO shanshan SUN Minglei yu Jingjun ZONG Guanghua School of Mechanical Engineering and Automation Beijing University of Aeronautics and Astronautics Beijing 100191 China

Large-deflection flexure pivot is widely used in high precision rotation application, but there are less flexure configurations and simple and convenient design methods, This paper presents a novel large-deflection curved-compliant annulus-shaped flexure pivot composed of six curved beam flexure elements. It can offer more than lO^angular stroke theoretically. Firstly, main-motion pseudo-rigid-body method is introduced to establish the flexure pivot model. Although pseudo-rigid-body method can be used to analyze the large-deformation flexure pivot performance, the method is definitely a laborious and difficult task for designing this novel flexure pivot. In order to simply the designing process, dimension-design graphs based on the parametric models and finite element analysis is presented. Using the dimension-design method as a tool, the designers can determine the optimal geometry rapidly, based on the stiffness and rotation demands of an annulus-shaped flexure pivot. Finally, dimension-design graph examples are given whose primary design aims to achieve a rotation stroke of annulus-shaped flexure pivot. The finite element analysis results show that the relative designing error between anticipative rotation stroke and graph design result is less than 4%. The dimensionless method used in designing annulus-shaped flexure pivot can reduce design process in both time and complexity. The novel annulus-shaped flexure pivot and dimension-design method are helpful supplement to configuration and design method of large-deflection flexure pivot.

关键词： annulus-shaped flexure pivot dimensionless design pseudo-rigid-body model

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Wall losses of oxygenated volatile organic compounds from oxidation of toluene:Effects of chamber volume and relative humidity

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Journal of Environmental Sciences 2022年第4期34卷 475-484页

作者： shanshan yu Long Jia Yongfu Xu Hailiang Zhang Qun Zhang yuepeng Pan State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Department of Atmospheric Chemistry and Environmental Sciences College of Earth and Planetary SciencesUniversity of Chinese Academy of SciencesBeijing 100049China

Vapor wall losses can affect the yields of secondary organic *** effects of surfaceto-volume(S/V)ratio and relative humidity(RH)on the vapor-wall interactions were investigated in this *** oxygenated volatile organic compounds(OVOCs)were generated from toluene-H_(2)O_(2)*** average gas to wall loss rate constant(k_(gw))of OVOCs in a 400 L reactor(S/V=7.5 m^(-1))is 2.47(2.41 under humid conditions)times higher than that in a 5000 L reactor(S/V=3.6 m-1)under dry *** contrast,the average desorption rate constant(k_(wg))of OVOCs in 400 L reactor is only 1.37(1.20 under humid conditions)times higher than that in 5000 L reactor under dry *** shows that increasing the S/V ratio can promote the wall losses of *** contrast,the RH effect on k_(gw)is not *** average k_(gw)value under humid conditions is almost the same as under dry conditions in the 400 L(5000 L)***,increasing RH can decrease the desorption *** average k_(wg)value under dry conditions is 1.45(1.27)times higher than that under humid conditions in the 400 L(5000 L)*** high RH can increase the partitioning equilibrium timescales and enhance the wall losses of OVOCs.

关键词： Vapor wall loss Surface-to-volume ratio Relative humidity Toluene Smog chamber Oxygenated volatile organic compounds

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Curcumin reduces inflammatory reactions following transient cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2011年第3期6卷 219-223页

作者： Zhao, Jing yu, shanshan Li, Lan Lin, Xuemei Zhao, Yong Chongqing Med Univ Dept Pathophysiol Chongqing 400016 Peoples R China Chongqing Med Univ Dept Pathol Chongqing 400016 Peoples R China

Inflammatory reactions are important pathophysiological mechanisms of ischemic brain injury. The present study analyzed the anti-inflammatory characteristics of curcumin via myeloperoxidase activity and nitric oxide content after 2-hour ischemia/24-hour reperfusion in Sprague Dawley rats. In addition, expressions of nuclear factor kappa B, tumor necrosis factor-α and interleukin-lβ protein were measured. Curcumin significantly reduced myeloperoxidase and nitric oxide synthase activities and suppressed expressions of nuclear factor kappa B, tumor necrosis factor-α, and interleukin-lβ in ischemia/reperfusion brain tissue. Results suggested that the neuroprotective effect of curcumin following cerebral ischemia/reperfusion injury could be associated with inhibition of inflammatory reactions.

关键词： curcumin inflammation tumor necrosis factor-a nuclear factor kappa B neuroprotection stroke ischemiaJreperfusion

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Sulforaphane protects primary cultures of cortical neurons against injury induced by oxygen-glucose deprivation/reoxygenation via anti-apoptosis

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Neuroscience Bulletin 2012年第5期28卷 509-516页

作者： Xuemei Wu Jing Zhao shanshan yu Yanlin Chen , Jingxian Wu Yong Zhao Department of Pathology Department of Pathophysiology Chongqing Medical University Chongqing 400016 China

Objective To determine whether sulforaphane （SFN） protects neurons against injury caused by oxygen-glucose deprivation/reoxygenation （OGD/R） and, if so, to investigate the possible mechanisms. Methods Primary cultures of neurons were prepared from the cerebral cortex of 1-day-old Sprague-Dawley rats. On days 5-6 in vitro, the neurons were exposed to OGD for 1 h, followed by reoxygenation for 24 h. Cells were treated with 0, 0.1, 0.2, 0.5, 1, 2.5, or 5 μmol/L SFN, with or without 10 μmol/L LY294002, a PI3K-specific inhibitor, during OGD/R （a total of 25 h）. After 24-h reoxygenation, MTT was used to assess viability and injury was assessed by Hoechst 33258/propidium iodide （PI） staining; immunofluorescence staining and Western blot were performed to detect molecular events associated with apoptosis. Results The MTT assay showed that 1 μmol/L SFN significantly increased viability, and Hoechst 33258/PI staining showed that the numbers of injured neurons were reduced significantly in the SFN group. Furthermore, immunofluorescence staining and Western blot showed that SFN increased Bcl-2 and decreased cleaved caspase-3 levels. Moreover, LY294002 inhibited the phosphorylated-Akt expression evoked by SFN, decreased Bcl-2 expression and increased cleaved caspase-3 expression. Conclusion SFN protects neurons against injury from OGD/R and this effect may be partly associated with an anti-apoptosis pathway.

关键词： sulforaphane oxygen-glucose deprivation apoptosis neuroprotection

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Reaction Kinetics and Secondary Organic Aerosol Composition Analysis of 2-Cyclohexen-1-one with NO_(3) Radicals

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Chemical Research in Chinese Universities 2024年第4期40卷 730-736页

作者： HU Lin TONG Shengrui XU Yanyong ZHANG Hailiang yu shanshan CHEN Meifang GE Maofa Structural Chemistry of Unstable and Stable Species Chinese Academy of Sciences Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190P.R.China College of Ecology and Environment Xinjiang UniversityUrumqi830017P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China

Unsaturated ketones are typical oxygenated volatile organic compounds(OVOCs)with high reactivity,and are important precursors in air *** sources of OVOCs are complex and include direct emissions and secondary oxidation formation of VOCs in the atmosphere.2-Cyclohexen-1-one is a widespread substance,and is derived from the industrial catalytic oxidation of *** this paper,we investigated the rate constants of the chemical reactions of 2-cyclohexen-1-one with NO_(3) radicals,which is(7.25±0.29)×10^(-15) cm^(3)·molecule^(-1)·s^(-1) at 298 K and under 1 atm(1 atm=101325Pa).It supplemented the kinetics of NO_(3) radicals database,and revealed its effects in the nighttime *** addition,the reaction products of 2-cyclohexen-1-one with NO_(3) radicals were detected by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS),which revealed a series of nitrate esters in the composition of the secondary organic aerosol(SOA),which may reduce atmospheric ***,the possible pathways for the generation of the products were developed.

关键词： Kinetics Unsaturated ketone Nitrate radical Secondary organic aerosol

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The Complete Sequence of Mitochondrial COII Gene of Fenneropenaeus chinensis and Its Applicability as a Marker for Phylogenetic Analysis

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Journal of Ocean University of China 2007年第2期6卷 187-192页

作者： yu shanshan KONG Xiaoyu LI yulong XU Hui Key Laboratory of Mariculture of Ministry of Education Ocean University of China Qingdao 266003 P. R. China

The complete mitochondrial cytochrome oxidase subunit Ⅱ （COⅡ） gene of Penaeinae shrimp Fenneropenaeus chinensis was cloned and sequenced. The gene is 688 bp in length and codes for 229 amino acids. It shows 83.2%, 87.0% and 83.8% sequence similarity to Marsupenaeus Japonicus, Penaeus monodon and Farfantepenaeus notialis, respectively. The A＋T content of the whole gene and that at the third position of codons are 64.7% and 78.2%, respectively. The phylogenetic relationship between F. chinensis and three other species representing genera Farfanatepenaeus, Marsupenaeus and Penaeus was analyzed. Results showed that the genetic distances among the four taxa ranged from 0.144 0 to 0.200 5, exceeding those estimated with COⅠ and partial 16S rRNA gene sequences among Marsupenaeus, Litopenaeus and Melicertus, and being therefore larger than the value among subgenera. It has been suggested that the COⅡ gene has a faster evolutionary rate than that of the COⅠ gene and partial 16S rRNA gene and could be used for phylogenetic analysis at genus or species level. The results of the present study indicated that Farfantepenaeus, Fenneropenaeus, Marsupenaeus and Penaeus are at a higher phylogenetic level than subgenus, which supports the opinion of the elevation of phylogenetic status of the four subgenera to genus level.

关键词： Fenneropenaeus chinensis COⅡ gene phylogenetic analysis

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Thermodynamic and kinetic mechanism of phase transformation of levofloxacin hydrochloride

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Particuology 2022年第7期20卷 59-70页

作者： Han Liu Xiunan Zhang Ting Wang Xin Huang Kui Chen Na Wang shanshan yu yuyuan Dong Hongxun Hao National Engineering Research Center for Industrial Crystallization Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China School of Chemical Engineering and Technology Hainan UniversityHaikou 570208China

In this work,thermodynamic and kinetic factors that affect formation and phase transformation process of different solid forms of levofloxacin hydrochloride were investigated in *** vapor sorption experiments(DVS)and varying temperature-powder X-ray diffraction(VT-PXRD)experiments were carried out to study moisture-dependent stability,thermal stability as well as the transformation process between Form I and Form *** water activities of levofloxacin hydrochloride were determined in temperature range of 5.0–45.0°*** spectroscopy was applied to in situ monitor the temperature-induced phase transformation and the hydration process of levofloxacin hydrochloride,and one possible mechanism consisting of multiple chemical equilibria was proposed to analyze the effect of thermodynamic and kinetic factors on the formation and transformation of different solid *** show that the anhydrate,Form II would transform to the monohydrate,Form I more easily with the increasing water *** the transition point moves toward higher water contents as the temperature *** results suggested that,except for thermodynamic factors,kinetic factors also play an essential role in controlling the solid forms of polymorphic compounds.

关键词： Levofloxacin hydrochloride Crystallization Phase transformation Hydrate

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