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Cell biology and immunology lessons taught by Legionella pneumophila

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Science China(Life Sciences) 2016年第1期59卷 3-10页

作者： Wenhan Zhu Zhao-qing luo Department of Biological Sciences Purdue University Department of Microbiology UT Southwestern Medical Center

Legionella pneumophila is a facultative intracellular pathogen capable of replicating within a broad range of hosts. One unique feature of this pathogen is the cohort of ca. 300 virulence factors(effectors) delivered into host cells via its Dot/Icm type IV secretion system. Study of these proteins has produced novel insights into the mechanisms of host function modulation by pathogens, the regulation of essential processes of eukaryotic cells and of immunosurveillance. In this review, we will briefly discuss the roles of some of these effectors in the creation of a niche permissive for bacterial replication in phagocytes and recent advancements in the dissection of the innate immune detection mechanisms by challenging immune cells with L. pneumophila.

关键词： Type IV secretion inflammasome effectors posttranslational modification vesicle transport

Control of subduction rate on Tonga-Kermadec arc magmatism

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Journal of Oceanology and Limnology 2018年第3期36卷 687-699页

作者： luo qing ZHANG Guoliang Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Laboratory of Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Deep-Sea Extreme Environment and Life Processes Center Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Dehydration/melting of oceanic crusts during returning to the mantle in subduction zones are related to origin of arc lavas. The factors that influence arc magmatism include compositions of the subducting slabs, mantle wedge and subduction rates. However, distinguishing these factors remains difficult and highly debated. Subducting rate is related to the total mass of inputs and controls thermal structure, thus plays a crucial role in arc magmatism. Here we explore the relationships between geochemical variations of arc lavas and convergence rates(increasing from 46 mm/a to the south to 83 mm/a to the northward) in the Tonga-Kermadec arc system. Data of geochemistry for lava samples from nine islands of this arc system are collected and compiled to investigate the role of subduction rate in arc magmatism. Lavas from the northern Tonga arc with a faster subduction rate show broadly lower concentrations of TiO_2 and highfield-strength elements(HFSEs, e.g. Nb, Ta, Zr, Hf), and higher Ba/Th, U/Th ratios than the Kermadec Arc to the south. Some of the Kermadec lavas show the highest values of Th/Nb ratio. We suggest that the northern Tonga arc with a higher subduction rate has been influenced by a stronger role of subductionreleased fluid, which results in stronger large-ion-lithophile elements(LILEs) and relatively weaker HFSEs contribution. It is interpreted that faster subduction rate tend to create a cooler subduction zone, leading to stronger dehydration subduction slab contribution with, thus, higher LILE/HFSE ratios of arc lavas. The conclusion contributes to a better understanding of arc magmatism, and ultimately the long-term chemical differentiation of the Earth. More supplementary geochemical data along Tonga-Kermadec arc and tests in other arcs are needed.

关键词： subduction rate arc magmatism Tonga-Kermadec Arc

Design of S-band re-entrant cavity BPM

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Nuclear Science and Techniques 2009年第3期20卷 133-139页

作者： luo qing SUN Baogen HE Duohui National Synchrotron Radiation Laboratory School of Nuclear Science and Technology University of Science and Technology of China Hefei 230029 China

An S-band cavity BPM is designed for a new injector for HLS (Hefei Light Source). It consists of two cavities that work on 2448 MHz: a re-entrant position cavity tuned to TM110 mode and a reference cavity tuned to TM010 mode. Cut-through waveguides are used as pickups to suppress the monopole signal. Simulations with different assumption of dimension change are performed to evaluate errors caused by mechanical error and give general tolerance. Design of electronics is given. Theoretical resolution of this design is 31 nm.

关键词： BPM 电子学单极信号理论

Weakly Algebraic Ideal Topology of Effect Algebras

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Acta Mathematica Sinica,English Series 2015年第5期31卷 787-796页

作者： qing Jun luo Guo Jun WANG School of Statistics Xi'an University of Finance and Economics School of Mathematics and Information Shaanxi Normal University

In this paper, we show that every weakly a uniform topology （weakly algebraic ideal topology, algebraic ideal of an effect algebra E induces for short） with which E is a first-countable, zero-dimensional, disconnected, locally compact and completely regular topological space, and the operation ＋ of effect algebras is continuous with respect to these topologies. In addition, we prove that the operation - of effect algebras and the operations A and V of lattice effect algebras are continuous with respect to the weakly algebraic ideal topology generated by a Riesz ideal.

关键词： Effect algebra weakly algebraic ideal uniform topology continuity

Convergence of the Cesaro Mean for Rational Orthonormal Bases

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Acta Mathematica Sinica,English Series 2009年第4期25卷 581-592页

作者： Ying Xiong FU luo qing LI Key Laboratory of Applied Mathematics Hubei ProvinceFaculty of Mathematics and Computer Science Hubei UniversityWuhan 430062 P. R. China

This paper deals with the convergence of the Cesaro mean for the rational orthonormal bases. Provided the set of zeroes of rational orthonormal bases is formed by a periodic repetition of the same finite sequence, the explicit expression of so-called block-Fejer kernel is available, and some properties of the block-Fejer kernel are discussed. Based on the convergence of the block-Cesaro mean, the convergence of Cesaro mean is also provided.

关键词： Cesaro mean trigonometric series rational orthonormal basis

Analysis and Testing of Microvibrations Produced by Momentum Wheel Assemblies

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Chinese Journal of Aeronautics 2012年第4期25卷 640-649页

作者： ZHOU Weiyong LI Dongxu luo qing LIU Kun College of Aerospace and Material Engineering National University of DeJense TechnologyChangsha 410073China

The microvibrations produced by momentum wheel assemblies（MWA） can degrade the performance of instruments with high pointing precision and stability on *** paper concentrates on analyzing and testing the microvibrations produced by *** analyze the disturbance sources produced by mass imbalance,structural mode,bearing irregularity and nonlinear stiffness,and random noise;then,test a well-balanced MWA by a highly sensitive measurement system consisting of a Kistler table and an optical *** results show that the test system has a resolution of less than 0.003 N in the frequency range of 3-300 *** dynamic imbalance of the MWA cannot excite the radial rocking mode,but there are dynamic amplifications when the poly-harmonic disturbances intersect with the structural *** at high rotational speed（〉3 000 rev/min）,the main disturbance sources of the MWA come from the bearing irregularity interacting with radial translation mode in the high frequency ***,bearing noise deserves more attention for the well-balanced MWA,and alternative of high quality bearings are proposed to reduce the microvibrations.

关键词： momentum wheel assemblies microvibration bearing irregularity mass imbalance vibration analysis

On the rate of convergence for multi-category classification based on convex losses

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Science China Mathematics 2007年第11期50卷 1529-1536页

作者： Hong CHEN luo-qing LI Faculty of Mathematics and Computer Science Hubei UniversityWuhan 430062China Faculty of Mathematics and Computer ScienceHubei UniversityWuhan 430062China

The multi-category classification algorithms play an important role in both theory and practice of machine *** this paper,we consider an approach to the multi-category classification based on minimizing a convex surrogate of the nonstandard misclassification *** bound the excess misclassification error by the excess convex *** construct an adaptive procedure to search the classifier and furthermore obtain its convergence rate to the Bayes rule.

关键词： misclassiflcation error consistency convergence rate

Beam emittance investigation in high brightness injector using different driver laser profiles

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 189-192页

作者： WANG XiaoHui SUN BaoGen luo qing School of Nuclear Science and Technology&National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

Beam emittance plays an important role in any accelerator, and it is a main parameter to judge the performance of an accelerator. Emittance optimization is an indispensable part in conditioning and operation of the facility. For a laser-driven high brightness injector, different time structure of the laser pulse has different effects on transverse emittance. In order to compare Gaussian and flat-top laser pulse, systematic simulations of 500 pC have been done. From the simulation results, one can see that flat-top pulse laser will yield smaller minimal transverse beam size and transverse beam emittance than Gaussian pulse laser.

关键词： transverse emittance laser pulse Gaussian flat-top phase space

Catch and arrest:exploiting the retromer by a Chlamydial effector

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Signal Transduction and Targeted Therapy 2017年第1期2卷 173-174页

作者： Zhao-qing luo Purdue Institute for Inflammation Immunology and Infectious Disease and Department of Biological SciencesPurdue UniversityWest LafayetteINUSA

Three recent papers,including one by Sun et al.1 in this issue of Signal Transduction and Targeted Therapy,analyze the structural basis of the inhibition of retromer function by the Chlamydial effector protein *** studies reveal that IncE recognizes a highly conserved region on SNX5,a component of the retromer,leading to the inhibition of retromer activity and the promotion of bacterial virulence.

关键词： Chlamydia al. promotion