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Coil to globule transition of homo- and block-copolymer with different topological constraint and chain stiffness

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Science China Chemistry 2015年第9期58卷 1471-1477页

作者： Wei Wang yanchun Li Zhongyuan lu State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical Chemistry Jilin University

In this paper, we present the coil-to-globule(CG) transitions of homopolymers and multiblock copolymers with different topology and stiffness by using molecular dynamics with integrated tempering sampling method. The sampling method was a novel enhanced method that efficiently sampled the energy space with low computational costs. The method proved to be efficient and precise to study the structural transitions of polymer chains with complex topological constraint, which may not be easily done by using conventional Monte Carlo method. The topological constraint affects the globule shape of the polymer chain, thus further influencing the CG transition. We found that increasing the topological constraint generally decreased CG transition temperature for homopolymers. For semiflexible chains, an additional first-order like symmetry-broken transition emerged. For block copolymers, the topological constraint did not obviously change the transition temperature, but greatly reduced the energy signal of the CG transition.

关键词： coil-to-globule transition topological constraint chain stiffness molecular dynamics

Comparison of polycyclic aromatic hydrocarbon pollution in Chinese and Japanese residential air

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Journal of Environmental Sciences 2011年第9期23卷 1512-1517页

作者： Hao lu Takashi Amagai Takeshi Ohura School of Environmental Science and Engineering Zhejiang Gongshang University Hangzhou Zhejiang 310012 China Institute for Environmental Sciences University of Shizuoka 52-1 Yada Shizuoka 422-8526 Japan

Comparative studies on polycyclic aromatic hydrocarbon （PAH） pollution in residential air of Hangzhou （China） and Shizuoka （Japan） were conducted in summer （August,2006） and winter （January,2007）.Total concentrations of 8 PAHs ranged from 7.1 to 320 ng/m 3 and 0.15 to 35 ng/m 3 in residential air of Hangzhou and Shizuoka,*** PAH concentrations in smoking houses were higher than that in nonsmoking *** nonsmoking houses,mothball emission and cooking practice were the emission sources of 2and 3-ring PAHs in Hangzhou,*** 2and 3-ring PAHs were from use of insect repellent,kerosene heating and outdoor environment in nonsmoking houses in *** 5and 6-ring PAHs in residential air were mainly from outdoor environment in both *** potencies of PAHs in residential air of Hangzhou were much higher than that in Shizuoka.

关键词： polycyclic aromatic hydrocarbons residential air emission source

Influences of open-central canopy on photosynthetic parameters and fruit quality of apples(Malus×domestica)in the Loess Plateau of China

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Horticultural Plant Journal 2022年第2期8卷 133-142页

作者： lu Lin Zimian Niu Chuangdao Jiang lu Yu Hongning Wang Meiyu Qiao College of Horticulture Shanxi Agricultural UniversityTaiyuanShanxi 030031China Key Laboratory of Plant Resources Institute of BotanyChinese Academy of SciencesBeijing 100093China Institute of Pomology Shanxi Agricultural UniversityTaiyuanShanxi 030031China

Although open-central canopy(OCC)is popular in apple(Malus×domestica)orchards in Loess Plateau of China,its relevant photosynthetic mechanisms have not been *** this study,changes in photosynthetically active radiation(PAR),gas exchange,chlorophyll fluorescence quenching and fruit quality in apple trees were measured in OCC and compared with those in the conventional condensed round and large canopy(RLC).Results showed that light intercepted at different orientations was 44%higher by OCC than that by *** improved light environment within OCC remarkably increased leaf maximum net photosynthetic rate(Pnmax)and significantly decreased stomatal *** high light,the ratio of photorespiratory rate to gross photosynthetic rate(Pr/Pg)in OCC was higher than that in ***,reversible component in non-photochemical quenching(r(qE))was increased,while irreversible component(r(qI))was decreased in OCC than in *** a result,the fruit quality in OCC was greatly boosted as evidenced by the significantly increased single fruit weight,fruit flesh firmness and fruit soluble solid contents and the sharply decreased fruit titratable acid *** intercepted by the canopy and the fruit soluble solid contents,leaf Pnmaxor single fruit weight were positively correlated,while PAR or Pnmaxwas negatively correlated with the fruit titratable acid ***,the improved crown light environment and the enhanced leaf photosynthetic performance and photoprotective capacity in OCC led to the boosted fruit quality.

关键词： Apple Open-central canopy Light environment Photosynthesis Thermal dissipation Photorespiration Fruit quality

Natural mineral photoelectric effect: mineral non-classical photosynthesis

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地学前缘 2020年

作者： lu Anhuai LI yan DING Hongrui WANG Changqiu XU Xiaoming LIU Feifei LIU Yuwei ZHU Ying LI yanzhang Beijing Key Laboratory of Mineral Environmental Function， School of Earth and Space Sciences， Peking University

Under the ever-present solar radiation， photosynthetic organisms on Earth evolved structurally-sophisticated photosynthetic systems. However， little attention has been paid to the inherent impact of sunlight illumination on the inorganic minerals widespread on the Earth surface. We discovered for the first time the solar energy conversion system of the “mineral coatings” on the Earth’s surface （aka “mineral membrane”）， which exerts potential oxygen-production and carbon-sequestration functions on the Earth surface. Our finding shed a light on the photoelectric effect and non-classical photosynthesis involving natural semiconducting minerals. In this contribution， we studied the semiconducting property and photoelectron energy of typical minerals in the “mineral membrane”， focusing primarily on the photoelectric effect in and oxygen-production/carbon-sequestration function of ferromanganese oxides， as well as relevant geological records. We propose that birnessite， goethite and hematite， the semiconducting minerals commonly found in the “mineral membrane”， can perform sensitive and stable photon-to-electron conversion under solar radiation. The non-classical mineral photosynthetic function we put forth is as follows: Solar energy utilization by inorganic minerals resembles photosynthesis in regarding to oxygen evolution and carbon fixing， and the “mineral membrane” may take part in both photocatalytic water-oxidation reaction and transformation of atmospheric CO2 into marine carbonate. In addition， minerals might as well have promoted photosynthesis in photosynthetic organisms. During the water-oxidation reaction， the inorganic cluster Mn4CaO5 of photosystem II cycles through redox intermediates that are analogous to birnessite both in structure and component. Thus， it is fair to postulate that birnessites could play a role in the initiation of the photosynthesis in cyanobacteria， as minerals could weaken the hydrogen bond strength and alter water properties， thus fa

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Time-dependent viscoelastic behavior of an LDPE melt

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Acta Mechanica Sinica 2006年第3期22卷 199-206页

作者： Shuxin Huang Chuanjing lu Yurun Fan Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200030 China State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

Two differential constitutive equations, i.e. Giesekus model and Johnson-Segalman model were employed here to predict the time-dependent viscoelastic behavior of an LDPE melt in thixotropy-loop experiments and step shear rate experiment. Multiple relaxation modes were adopted, and the parameters used to describe the nonlinear viscoelasticity in the two models were obtained by fitting the shear-thinning viscosity. The predictions on those transient shear characteristics by the two models are found in qualitative agreement with our previous experiments. JohnsonSegalman model predicts oscillation behavior in the thixotropy-loop and step shear rate experiments, whereas Giesekus model does not. Both models predict higher shear stresses than the experimental data in the case of long time shearing, implying that both models are not able to completely characterize the time-dependent shear stress of the melt at high shear rate.

关键词： Transient shear tests LDPE Time-dependent viscoelastic Giesekus model Johnson-Segalman model

Novel load balancing DHT scheme for the heterogeneous system

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Journal of Systems Engineering and Electronics 2008年第4期19卷 835-842页

作者： Li Yujun lu Xianliang Hou Mengshu School of Computer Science and Engineering Univ. of Electronics Science and Technology of China Chengdu 610054 P. R. China

The capacities of the nodes in the peer-to-peer system are strongly heterogeneous, hence one can benefit from distributing the load, based on the capacity of the nodes. At first a model is discussed to evaluate the load balancing of the heterogeneous system, and then a novel load balancing scheme is proposed based on the concept of logical servers and the randomized binary tree, and theoretical guarantees are given. Finally, the feasibility of the scheme using extensive simulations is proven.

关键词： distributed hash table heterogeneity randomized binary tree load balancing

基于顶空-气相色谱-离子迁移谱探究不同成熟期番茄果实风味的差异

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食品科学 2025年第2期46卷 138-147页

作者：付小辉施露孙清珍董晓星朴凤植杜南山河南农业大学园艺学院河南郑州450046 江苏省食品质量安全重点实验室江苏省农业科学院农产品质量安全与营养研究所江苏南京210014

以野生型番茄‘Alisa Craig’为试材,采用高效液相色谱和顶空-气相色谱-离子迁移谱等方法,从代谢和转录水平分析挥发性代谢物质在绿熟期、转色期、坚熟期和完熟期4个成熟阶段的变化趋势。结果表明:随果实成熟,柠檬酸、番茄红素及β-胡... 详细信息

以野生型番茄‘Alisa Craig’为试材,采用高效液相色谱和顶空-气相色谱-离子迁移谱等方法,从代谢和转录水平分析挥发性代谢物质在绿熟期、转色期、坚熟期和完熟期4个成熟阶段的变化趋势。结果表明:随果实成熟,柠檬酸、番茄红素及β-胡萝卜素的含量逐渐增加,苹果酸和β-隐黄质含量则逐渐降低。番茄果实在4个时期共检测到81种挥发性代谢物质,这些物质的总量呈以下规律:完熟期>坚熟期>转色期>绿熟期。进一步将筛选到的40种差异代谢物与品质指标进行相关性分析,发现番茄红素与挥发性代谢物质6-甲基-5-庚烯-2-酮呈正相关。此外,叶绿素降解相关基因SlSGR1、类胡萝卜素代谢相关基因SlPSY1在转色期表达量骤增,与(E)-2-己烯醛变化趋势相似,类胡萝卜素代谢相关基因SlLCYb和SlBCH2则均在完熟期表达量最高,与6-甲基-5-庚烯-2-酮的变化趋势一致。进一步推测,番茄果实在成熟过程中可能通过调控类胡萝卜素代谢相关基因的表达,从而改变果实风味。研究结果将有助于全面了解番茄果实成熟的内在物质基础,为果实成熟过程风味的代谢调控以及改善果实品质提供新的理论依据。

关键词：番茄成熟期品质挥发性化合物

GSNOR negatively regulates the NLRP3 inflammasome via S-nitrosation of MAPK14

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Cellular & Molecular Immunology 2024年第6期21卷 561-574页

作者： Qianjin Liu Lijin Jiao Mao-Sen Ye Zhiyu Ma Jinsong Yu Ling-yan Su Wei-Yin Zou lu-Xiu yang Chang Chen Yong-Gang Yao Key Laboratory of Genetic Evolution&Animal Models and Key Laboratory of Animal Models&Human Disease Mechanisms of Yunnan ProvinceKunming Institute of ZoologyChinese Academy of Sciences650201KunmingYunnanChina Kunming College of Life Science University of Chinese Academy of Sciences650204KunmingYunnanChina Key Laboratory of Biomacromolecules(CAS) National Laboratory of BiomacromoleculesCAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of Sciences100101BeijingChina KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases Kunming Institute of ZoologyChinese Academy of Sciences650201KunmingYunnanChina National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility) National Resource Center for Non-Human PrimatesKunming Institute of ZoologyChinese Academy of Sciences650201KunmingChina

Hyperactivation of the NLRP3 inflammasome has been implicated in the pathogenesis of numerous ***,the precise molecular mechanisms that modulate the transcriptional regulation of NLRP3 remain largely *** this study,we demonstrated that S-nitrosoglutathione reductase(GSNOR)deficiency in macrophages leads to significant increases in the Nlrp3 and Il-1βexpression levels and interleukin-1β(IL-1β)secretion in response to NLRP3 inflammasome ***,in vivo experiments utilizing Gsnor^(−/−)mice revealed increased disease severity in both lipopolysaccharide(LPS)-induced septic shock and dextran sodium sulfate(DSS)-induced colitis ***,we showed that both LPS-induced septic shock and DSS-induced colitis were ameliorated in Gsnor^(−/−)Nlrp3^(−/−)double-knockout(DKO)***,GSNOR deficiency increases the S-nitrosation of mitogen-activated protein kinase 14(MAPK14)at the Cys211 residue and augments MAPK14 kinase activity,thereby promoting Nlrp3 and Il-1βtranscription and stimulating NLRP3 inflammasome *** findings suggested that GSNOR is a regulator of the NLRP3 inflammasome and that reducing the level of S-nitrosylated MAPK14 may constitute an effective strategy for alleviating diseases associated with NLRP3-mediated inflammation.

关键词： GSNOR S-nitrosation NLRP3 inflammasome MAPK14 Septic shock Colitis

Design of a memory polynomial predistorter for wideband envelope tracking amplifiers

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Journal of Systems Engineering and Electronics 2011年第2期22卷 193-199页

作者： Jing Zhang Songbai He lu Gan School of Electronic Engineering University of Electronic Science and Technology of China Chengdu 610054 P. R. China

Efficiency and linearity of the microwave power amplifier are critical elements for mobile communication systems. A memory polynomial baseband predistorter based on an indirect learning architecture is presented for improving the linearity of an envelope tracing （ET） amplifier with application to a wireless transmitter. To deal with large peak-to-average ratio （PAR） problem, a clipping procedure for the input signal is employed. Then the system performance is verified by simulation results. For a single carrier wideband code division multiple access （WCDMA） signal of 16-quadrature amplitude modulation （16-QAM）, about 2% improvement of the error vector magnitude （EVM） is achieved at an average output power of 45.5 dBm and gain of 10.6 dB, with adjacent channel leakage ratio （ACLR） of -64.55 dBc at offset frequency of 5 MHz. Moreover, a three-carrier WCDMA signal and a third-generation （3G） long term evolution （LTE） signal are used as test signals to demonstrate the performance of the proposed linearization scheme under different bandwidth signals.

关键词： envelope tracking memory polynomial predistorter,indirect learning architecture power amplifier memory effects.