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Whitefly feeding behavior and retention of a foregut-borne crinivirus exposed to artificial diets with different pH values

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Insect Science 2017年第6期24卷 1079-1091页

作者： Jaclyn S. Zhou Angel Y. S. Chen Martin Drucker Nicole H. Lopez Alyssa Carpenter James C. K. ng Department of Plant Pathology and Microbiology and Center for Disease Vector Research University of California Riverside California USA INRA UMR BGPI Plant Pathogen Interactions Montpellier Cedex 5 France Barry University Miami Florida USA east Stroudsburg University E. Stroudsburg Pennsylvania USA

Transmission of plant viruses by phytophagous hemipteran insects encompasses complex interactions underlying a continuum of processes involved in virus acquisition, retention and inoculation combined with vector feeding behavior. Here, we investigated the effects of dietary pH on whitefly （Bemisia tabaci） feeding behavior and release of Lettuce infectious yellows virus （LIYV） virions retained in the vector＇s foregut. electrical penetration graph analysis revealed that variables associated with whitefly probing and ingestion did not differ significantly in pH （4, 7.4, and 9） adjusted artificial diets. To investigate virus retention and release, whiteflies allowed to acquire LIYV virions in a pH 7.4 artificial diet were fed pH 4, 7.4, or 9 virion-free artificial （clearing） diets. Immunofluorescent localization analyses indicated that virions remained bound to the foreguts of approximately 20%-24% of vectors after they fed on each of the 3 pH- adjusted clearing diets. When RNA preparations from the clearing diets were analyzed by reverse transcription （RT） nested-PCR and, in some cases, real-time qPCR, successful amplification of LIYV-specific sequence was infrequent but consistently repeatable for the pH 7.4 diet but never observed for the pH 4 and 9 diets, suggesting a weak pH-dependent effect for virion release. Viruliferous vectors that fed on each of the 3 pH-adjusted clearing diets transmitted LIYV to virus-free plants. These results suggest that changes in pH values alone in artificial diet do not result in observable changes in whitefly feeding behaviors, an observation that marks a first in the feeding of artificial diet by whitefly vectors; and that there is a potential causal and contingent relationship between the pH in artificial diet and the release/inoculation of foregut bound virions.

关键词： Crinivirus dietary pH inoculation noncirculative semipersistent transmission retention whitefly

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根据计算结构因子重新指定镍(II)8-羟基喹啉的两个络合物(英文)

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物理化学学报 2001年第11期17卷 1040-1044页

作者： ng Seikweng 胡盛志马来亚大学研究生院厦门大学化学系厦门361005

晶体学研究曾认为分子式是NaNiQ2HQCLO4的结构并不含有钠而应为H3ONiQCLO4.相似地,稀土-Ni络合物YQHQ2NiQ3CLO4也不含有钇而应为H3ONi2Q3CLO4.晶体结构描述的修正系根据文献报导的原子坐标计算结构因子所导出的结果.

关键词：结构修正镍(Ⅱ)络合物计算结构因子 8-羟基喹啉

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2D氮化碳:通过调节非金属硼掺杂C_(3)N_(5)阐明宽酸性及碱性pH范围的光催化析氢的反应机理

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Chinese Journal of Catalysis 2023年第4期47卷 150-160页

作者： Sue-Faye ng 陈星竹 Joel Jie Foo 熊墨 Wee-Jun Ong 厦门大学马来西亚分校能源与化学工程学院马来西亚雪兰莪厦门大学马来西亚分校纳米能源与催化技术卓越中心(CONNeCT) 马来西亚雪兰莪 KAUST催化中心阿卜杜拉国王科技大学沙特阿拉伯吉达西安交通大学物理学院教育部物质非平衡合成与调控重点实验室陕西西安710049 固体表面物理化学国家重点实验室厦门大学化学化工学院福建厦门361005 厦门大学深圳研究院广东深圳518057 厦门大学古雷石化研究院福建漳州363216

太阳能驱动水裂解产氢是一种绿色能源技术,用于制备可再生和零碳排放燃料以实现可持续能源生产.近期,氮化碳(g-C_(3)N_(4))同素异形体C_(3)N_(5)的出现克服了g-C_(3)N_(4)的固有缺点,如光生载流子快速复合和可见光吸收差,而导致极低的... 详细信息

太阳能驱动水裂解产氢是一种绿色能源技术,用于制备可再生和零碳排放燃料以实现可持续能源生产.近期,氮化碳(g-C_(3)N_(4))同素异形体C_(3)N_(5)的出现克服了g-C_(3)N_(4)的固有缺点,如光生载流子快速复合和可见光吸收差,而导致极低的光催化效率.本文将硼掺杂剂通过原子替换或间隙掺杂的方式引入到C_(3)N_(5)体系中,并利用密度泛函理论对纯C_(3)N_(5)和硼掺杂C_(3)N_(5)体系进行计算,考察了硼原子对C_(3)N_(5)电子和光学性能的影响以及其催化析氢反应(HeR)机理.热力学计算结果表明,硼原子掺杂在C_(3)N_(5)体系中是可行且有利的.在N_(3)位氮原子被硼原子取代(BN_(3)-C_(3)N_(5))后,带隙(0.6 e V)变窄.与纯C_(3)N_(5)相比,硼掺杂剂通过Volmer Tafel和Volmer Heyrovsky机制降低了酸性和碱性介质中HeR反应中决定步骤的反应能垒.BN_(3)-C_(3)N_(5)表面的氢吸附吉布斯自由能(0.11 e V)与Pt/C催化剂(-0.09 e V)相当.综上,非金属掺杂碳可提高氮化物的催化性能,对未来该方向研究提供一定借鉴.

关键词：氮化碳同素异形体析氢反应密度泛函理论酸性介质碱性介质光催化

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Ascending aortic dilatation rate after transcatheter aortic valve replacement in patients with bicuspid and tricuspid aortic stenosis: A multidetector computed tomography follow-up study

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World Journal of emergency Medicine 2019年第4期10卷 197-204页

作者： Yu-xin He Jia-qi Fan Qi-feng Zhu Qi-jing Zhou Ju-bo Jiang Li-han Wang Stella ng Xian-bao Liu Jian-an Wang Department of Cardiology the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Department of Radiology the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China

BACKGROUND: Current data is lacking about the progression of ascending aortic dilatation after transcatheter aortic valve replacement(TAVR) in aortic stenosis(AS) patients with bicuspid aortic valve(BAV) and tricuspid aortic valve(TAV). This study aims to assess the ascending aortic dilatation rate(mm/year) after TAVR in patients with BAV versus TAV using a multidetector computed tomography(MDCT) fol ow-up and to determine the predictors of ascending aortic dilatation ***: Severe AS patients undergoing TAVR from March 2013 to March 2018 at our center with MDCT follow-ups were included. BAV and TAV were identified using baseline MDCT. Baseline and follow-up MDCT images were analyzed,and the diameters of ascending aorta were measured. Study end point is ascending aortic dilatation rate(mm/year). Furthermore,factors predicting ascending aortic dilatation rate were also ***: Two hundred and eight patients were included,comprised of 86 BAV and 122 TAV patients. Five,4,3,2,and 1-year MDCT follow-ups were achieved in 7,9,30,46,and 116 patients. The ascending aortic diameter was significantly increased after TAVR in both BAV group(43.7±4.4 mm vs. 44.0±4.5 mm;Pever,no difference of ascending aortic dilatation rate was found between BAV and TAV group(0.2±0.8 mm/year vs. 0.3±0.8 mm/year,P=0.592). Multivariate linear regression revealed paravalvular leakage(PVL) grade was independently associated with ascending aortic dilatation rate in the whole population and BAV group,but not TAV group. No aortic events occurred during ***: Ascending aortic size continues to grow after TAVR in BAV patients,but the dilatation rate is mild and comparable to that of TAV patients. PVL grade is associated with ascending aortic dilatation rate in BAV patients post-TAVR.

关键词： Transcatheter aortic valve replacement Aortic dilatation Bicuspid aortic valve

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关于具有测边导坑和有限岩石覆盖层的隧道开口的离散分析（英文）

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2018年第4期19卷 255-265页

作者： Chia Weng BOON Chee Wei NeO David Chew Chiat ng Victor Chee Wee Ong One Smart engineering Pte Ltd. 658065 Singapore

目的:针对新加坡的花岗岩地质结构,研究将典型马蹄形隧道挖掘成双拱隧道时岩石支撑的设计问题。利用离散元法分析侧边导坑对隧道主体开口的影响。创新点:1.基于平面应变假设,提出一个针对性的离散元模型以分析侧边导坑的设置对主体隧道... 详细信息

目的:针对新加坡的花岗岩地质结构,研究将典型马蹄形隧道挖掘成双拱隧道时岩石支撑的设计问题。利用离散元法分析侧边导坑对隧道主体开口的影响。创新点:1.基于平面应变假设,提出一个针对性的离散元模型以分析侧边导坑的设置对主体隧道支撑的影响;2.此模型适用于解决底下长跨度开口的支撑设计问题,如大众捷运系统隧道和紧贴式双孔隧道的建造,补充了传统经验主义的设计方法。方法:1.采用离散元法对马蹄形隧道开口支撑问题进行非连续分析;2.采用二维平面应变模型简化问题。结论:1.离散元法可用于分析有限岩石覆盖层的失效机制,单隧道支撑要求以及增加侧边导坑后的支撑要求;2.模型计算结果显示,侧边导坑的挖掘使得支柱总的螺栓连接作用力增加了一倍。

关键词：岩石覆盖层双隧道侧边导坑支柱离散元法

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雌激素受体β转录激活区内丝氨酸105位点磷酸化抑制子宫内膜异位症进程的研究

雌激素受体β转录激活区内丝氨酸105位点磷酸化抑制子宫内膜异位...

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作者： ng TAI WeI 厦门大学

学位级别：硕士

研究背景及意义:子宫内膜异位症(endometriosis,eM),简称内异症,为育龄期妇女的常见病,是指具有活性的子宫内膜种植于宫腔以外部位后形成的异位病灶,导致患者出现慢性盆腔痛、不孕及痛经等临床症状。内异症是种雌激素依赖性疾病,大量研... 详细信息

研究背景及意义:子宫内膜异位症(endometriosis,eM),简称内异症,为育龄期妇女的常见病,是指具有活性的子宫内膜种植于宫腔以外部位后形成的异位病灶,导致患者出现慢性盆腔痛、不孕及痛经等临床症状。内异症是种雌激素依赖性疾病,大量研究证据表明,内异症患者异位病灶中雌激素受体β(eRβ)的表达明显高于正常子宫内膜组织[1,2]。eRβ是重要的转录因子,可通过启动基因转录发挥生物学效应,而在转录的过程中,磷酸化扮演了重要的角色。位于eRβ结构上转录激活区-1(AF-1)中丝氨酸S105位点的磷酸化可通过调控eRβ的转录活性抑制细胞的迁移及侵袭能力,但其调控机理和相关的信号通路尚不明确。探讨S105位点磷酸化的分子机理对揭示eRβ调控内异症的发病机制,寻找潜在的内异症治疗靶点有着重大的意义。目的:本论文以eRβ磷酸化为研究对象,探索eRβ S105磷酸化水平在内异症中的改变。通过构建eRβS105磷酸化位点突变型细胞,研究该位点对eRβ转录活性及细胞生物学行为的影响。检测在促炎因子白介素(IL-1β)及抑炎因子脂氧素A4(lipoxin A4,LXA)处理下原代子宫内膜细胞中eRβ S105磷酸化程度的变化,探索LXA抑制内异症的机制是否通过调节eRβ S105位点的磷酸化。方法:收集子宫内膜异位症患者(研究组)及输卵管性不孕患者的内膜组织(对照组),通过蛋白免疫印迹(Western blot)以及免疫组化(IHC)等实验方法探索eRβ p-S105蛋白在子宫内膜异位症患者的异位内膜、在位内膜及对照组子宫内膜的分布,结合临床数据综合分析eRβ S105磷酸化的临床意义。构建并且鉴定eRβ S105位点突变体eRβ-S105A(失活型)及eRβ-S105e(持续激活型)。通过MTS,细胞划痕及Transwell等实验研究eRβ S105磷酸化对细胞生物学行为的影响以及通过荧光素酶报告基因探索LXA、SB203580与eRβ p-S105之间的相互作用。分离并培养内异症患者子宫内膜在位腺上皮细胞(以下简称为eeCs),予以白介素(IL-1β)、脂氧素(LXA)及MAPK抑制剂(SB203580、PD98059、SP600125)个别处理或共同刺激,以Western blot法检测细胞中eRβp-S105程度的变化,明确LXA是否通过p38信号通路调控eRβ S105磷酸化水平。结果:eRβ S105位点的磷酸化程度在内异症患者的异位内膜、在位内膜以及对照组中存在差异,对照组中磷酸化程度明显低于内异症组,且差异具有统计学意义(*peRβ S105位点磷酸化程度与年龄,不孕、血清中CA125、CA199值无显著差异,但与内异症r-AFS分期呈负相关性。我们构建了 eRβS105野生型(WT)、eRβS105位点突变体eRβ-S105A(失活型)及eRβ-S105e(持续激活型)并以此为细胞模型,研究发现在eRβ S105位点持续磷酸化的状态下,eRβ的转录活性显著升高,导致细胞的增殖及迁移能力被抑制。而在eRβ-S105位点磷酸化失活后,细胞的侵袭及迁移能力明显增强,同时促进了上皮-间质转化现象。在子宫内膜细胞中,IL-1β可以显著性上调eRβp-S105及p-p38MAPK蛋白水平,且上升呈现时间及浓度梯度依赖性,而在LXA预处理后可以明显抑制IL-1β诱导eRβ p-S105及p-p38 MAPK的效应。同时p38 MAPK抑制剂可明显阻断IL-1β诱导eRβp-S105的作用。结论:eRβ S105的磷酸化程度在内异症患者中明显增高,且与内异症轻重程度呈负相关趋势,eRβ S105去磷酸化后细胞的迁移及侵袭能力明显提高,提示S105的磷酸化对内异症的进程有保护作用。LXA可通过p38信号通路调节eRβ转录激活区-1上S105位点的磷酸化水平抑制子宫内膜异位症的发展。

关键词：子宫内膜异位症雌激素受体磷酸化脂氧素 p38信号通路

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Dispersion in oscillatory electro-osmotic flow through a parallel-plate channel with kinetic sorptive exchange at walls

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Journal of Hydrodynamics 2014年第3期26卷 363-373页

作者： SOng Jie 吴朝安 LAW Wing-Keung Adrian School of Civil and environmental engineering Nanyang Technological University Department of Mechanical engineering The University of Hong Kong

Dispersion in time-oscillatory electro-osmotic flows in a slit micro-channel under the effect of kinetic sorptive exchange at walls is theoretically investigated using the homogenization method. The two walls of the channel are considered to be made up of different materials, and therefore have different zeta potentials and sorption coefficients. A general expression for the Taylor dispersion coefficient under different zeta potentials as well as various sorption conditions at the walls is derived analytically. The dispersion coefficient is found to be dependent on the oscillation frequency, the Debye parameter, the species partition coefficient, the reaction kinetics and the ratio of the wall potentials. The results demonstrate that the presence of wall sorption tends to enhance the dispersion when the oscillation frequency is low, but the effect is negligible in high-frequency oscillatory flows. Moreover, it is found that the dispersion coefficient could be significantly changed by adjusting the relative wall potentials for low-frequency flows.

关键词： oscillatory electro-osmotic flows dispersion sorptive walls homogenization method

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NUMeRICAL ANALYSIS OF THe PeRFORMANCe OF HORIZONTAL AND WAVY SUBSURFACe FLOW CONSTRUCTeD WeTLANDS

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Journal of Hydrodynamics 2011年第3期23卷 339-347页

作者： WAng Jun HUAng Sui-liang He Cheng-da ng Chiu-On College of environmental Science and engineering Nankai University Tianjin 300071 China Numerical Simulation Group for Water environment Key Laboratory of Pollution Processes and EnvironmentalCriteria of Ministry of Education Tianjin Key Laboratory of Environmental Remediation and Pollution ControlCollege of Environmental Science and Engineering Nankai University Tianjin 300071 China College of environmental Science and engineering Yangzhou University Yangzhou 225009 China Department of Mechanical engineering The University of Hong Kong Hong Kong China

A three-dimensional numerical model is proposed for modeling the TP transport in the Horizontal Subsurface Flow （HSSF） and Wavy subsurface Flow （WSSF） constructed wetland in this article. Both numerical simulations and physical experiments indicate that the removal efficiency of WSSF is higher than that of HSSF. The difference ofperforrnance in removing pollutants, e.g., Total Phosphorus （TP）, between HSSF and WSSF is numerically analyzed from three interactive aspects, that is, the hydraulic behavior, the substrate and the plant roots. It is shown that the dead zone volume in WSSF is smaller than in HSSF with less short circuiting. The soil in the top layer is more used in WSSF than in HSSF. The TP uptake by the plant roots in WSSF is higher than that in HSSF.

关键词： numerical model constructed wetland hydraulic behavior Retention Time Distribution (RTD) removal efficiency

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miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold e.Beyreuther F.-e.Brack F.Kroll J.Pawelke J.D.Schilz M.Schneider U.Schramm M.e.P.Umlandt K.Zeil T.Ziegler J.Metzkes-ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

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estimating canopy closure density and above-ground tree biomass using partial least square methods in Chinese boreal forests

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Journal of Forestry Research 2012年第2期23卷 191-196页

作者： LeI Cheng-liang JU Cun-yong CAI Ti-jiu J1ng Xia WeI Xiao-hua DI Xue-ying School of Forestry Northeast Forestry UniversityHarbin 150040P.R.China College of Geomatics Xi'an University of Science and TechnologyXi'an 710054P.R.China Department of earth and environmental Science University of BritishColumbia(Okanagan)3333 University wayKelownaBritish Colum-biaCanadaV1V 1V7.

Boreal forests play an important role in global environment systems. Understanding boreal forest ecosystem structure and function requires accurate monitoring and estimating of forest canopy and biomass. We used partial least square regression （PLSR） models to relate forest parameters, i.e. canopy closure density and above ground tree biomass, to Landsat eTM＋ data. The established models were optimized according to the variable importance for projection （VIP） criterion and the bootstrap method, and their performance was compared using several statistical indices. All variables selected by the VIP criterion passed the bootstrap test （p〈0.05）. The simplified models without insignificant variables （VIP 〈1） performed as well as the full model but with less computation time. The relative root mean square error （RMSe%） was 29% for canopy closure density, and 58% for above ground tree biomass. We conclude that PLSR can be an effective method for estimating canopy closure density and above ground biomass.

关键词： above-ground tree biomass bootstrap method canopy clo- sure density partial least square regression (PLSR) VIP criterion

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