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Engineering for Inclusion:Empowering Individuals with Physical and Neurological Differences through Engineering Invention,Research,and Development
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作者 Peter T.Cummings Philippe M.Fauchet +7 位作者 Michael Goldfarb Martha W.M.Jones Maithilee Kunda Jonathan B.Perlin Nilanjan Sarkar Keivan G.Stassun Zachary E.Warren Karl E.Zelik 《Engineering》 SCIE EI 2021年第2期141-143,共3页
1.Background The use of engineering tools,design,research,and thinking to create environments and capabilities whereby individuals who are currently under-employed or unemployed due to a physical disability(e.g.,amput... 1.Background The use of engineering tools,design,research,and thinking to create environments and capabilities whereby individuals who are currently under-employed or unemployed due to a physical disability(e.g.,amputation or spinal cord injury)or neurological difference(e.g.,autism)are enabled to become fully productive and employed members of society has been the implicit goal of decades of research at Vanderbilt University and elsewhere.At Vanderbilt University,progress in these areas has been greatly facilitated by the proximity of the School of Engineering to the world-class Vanderbilt University Medical Center and the resulting close collaboration between engineering and medical researchers. 展开更多
关键词 HAS environments power
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A novel multi-shot target platform for laser-driven laboratory astrophysics experiments 被引量:2
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作者 Pablo Perez-Martin Irene Prencipe +25 位作者 Manfred Sobiella Fabian Donat Ning Kang Zhiyu He Huiya Liu Lei Ren Zhiyong Xie Jun Xiong Yan Zhang Florian-Emanuel Brack MichalČervenák Pavel Gajdoš Lenka Hronová Kakolee Kaniz Michaela Kozlová Florian Kroll Xiayun Pan Gabriel Schaumann Sushil Singh MichalŠmíd Francisco Suzuki-Vidal Panzheng Zhang Jinren Sun Jianqiang Zhu Miroslav Krůs Katerina Falk 《High Power Laser Science and Engineering》 SCIE EI CAS CSCD 2023年第2期11-19,共9页
A new approach to target development for laboratory astrophysics experiments at high-power laser facilities is presented.With the dawn of high-power lasers,laboratory astrophysics has emerged as a field,bringing insig... A new approach to target development for laboratory astrophysics experiments at high-power laser facilities is presented.With the dawn of high-power lasers,laboratory astrophysics has emerged as a field,bringing insight into physical processes in astrophysical objects,such as the formation of stars.An important factor for success in these experiments is targetry.To date,targets have mainly relied on expensive and challenging microfabrication methods.The design presented incorporates replaceable machined parts that assemble into a structure that defines the experimental geometry.This can make targets cheaper and faster to manufacture,while maintaining robustness and reproducibility.The platform is intended for experiments on plasma flows,but it is flexible and may be adapted to the constraints of other experimental setups.Examples of targets used in experimental campaigns are shown,including a design for insertion in a high magnetic field coil.Experimental results are included,demonstrating the performance of the targets. 展开更多
关键词 high magnetic fields laboratory astrophysics laser-plasma interaction magnetized plasmas target design
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Experimental exploration and research prospect of physical bases and functional characteristics of meridians 被引量:15
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作者 Lun Fei Huansheng Cheng +8 位作者 Deheng Cai Shixun Yang Jianrong Xu Eryu Chen Ruishan Dang Guanghong Ding Xueyong Shen Yi Tang et al. 《Chinese Science Bulletin》 SCIE EI CAS 1998年第15期1233-1252,共20页
The physical basis of meridians and acupoints (acupuncture points) is in a complex system mainly of connective tissue and interwoven with the blood capillaries, nerves, lymph vessels,etc. Elements of Ca, P, K, Fe, Zn,... The physical basis of meridians and acupoints (acupuncture points) is in a complex system mainly of connective tissue and interwoven with the blood capillaries, nerves, lymph vessels,etc. Elements of Ca, P, K, Fe, Zn, Mn, etc are found concentrated in the deep connective tissue structures in locations corresponding to acupoints. On this physical basis, the specific waveband of high efficiency for transmission of infrared rays exists in the collagenous fibre in a liquid crystal state. The development direction and new idea of researching on acupuncture and meridians are discussed. 展开更多
关键词 MERIDIANS CONNECTIVE tissue structures CALCIUM BANK infrared RAY transmission.
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SUMMARY TABLES OF PARTICLE PROPERTIES Extracted from the Particle Listings of the Review of Particle Physics 被引量:15
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作者 C. Patrignani 《Chinese Physics C》 SCIE CAS CSCD 2016年第10期29-116,共88页
Particle Data Group C. Patrignani, K. Agashe, G. Aielli, C. Amsler, M. Antonelli, D.M. Asner H. Baer, Sw. Banerjee, R.M. Barnett, T. Basaglia, C.W. Bauer, J.J. Beatty, V.I. Belousov, J. Beringer, S. Bethke, H. Bichsel... Particle Data Group C. Patrignani, K. Agashe, G. Aielli, C. Amsler, M. Antonelli, D.M. Asner H. Baer, Sw. Banerjee, R.M. Barnett, T. Basaglia, C.W. Bauer, J.J. Beatty, V.I. Belousov, J. Beringer, S. Bethke, H. Bichsel, O. Biebel, E. Blucher, G. Brooijmans, O. Buchmueller, V. Burkert, M.A. Bychkov, R.N. Cahn, 展开更多
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Enhanced Electron–Electron Entanglement in Few-Cycle Laser-Atom Interactions
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作者 Jingyu Zhang Zhifeng Cao +2 位作者 Xiaolei Hao Weidong Li Jing Chen 《Chinese Physics Letters》 2025年第11期60-74,共15页
The rapid advancements of ultrafast intense laser technology have opened new avenues for investigating entanglement in laser-induced systems. However, the application of these advances in quantum technology requires a... The rapid advancements of ultrafast intense laser technology have opened new avenues for investigating entanglement in laser-induced systems. However, the application of these advances in quantum technology requires a reliable and universally applicable method for enhancing and regulating entanglement. Here we demonstrate how a few-cycle intense laser field can significantly enhance the degree of entanglement compared to its multi-cycle counterpart, using the example of electron–electron entanglement of orbital angular momentum(OAM) states in recollision-excitation non-sequential double ionization of Ar atoms. By confining the ionization dynamics to a specific narrow time window, the few-cycle pulse purifies the electron trajectories, thereby ensuring high coherence between entangled OAM channels and enhancing entanglement. Furthermore, the degree of entanglement can be efficiently modulated by varying the carrier envelope phase of the few-cycle laser pulse, which is achieved by altering the population across OAM channels. Optimizing coherence through electron trajectory purification with a designed specific temporal waveform of laser field provides a general pathway for enhancing entanglement in laser-induced systems. 展开更多
关键词 ultrafast intense laser technology orbital angular momentum electron electron entanglement orbit enhance degree entanglement few cycle laser enhancing regulating entanglement quantum technology electron electron entanglement
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Tunable Topological Floquet Bound States in the Continuum in a Periodically Driven Double SSH Chain
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作者 Xian Duan Ruozhen Wang +3 位作者 Bo Zhu Zhi Tan Honghua Zhong Shu Chen 《Chinese Physics Letters》 2025年第9期77-87,共11页
We propose a novel approach to generate and manipulate topological Floquet bound states in the continuum(BICs)via a class of systems constructed by coupling two identical periodically driven one-dimensional Su-Schrief... We propose a novel approach to generate and manipulate topological Floquet bound states in the continuum(BICs)via a class of systems constructed by coupling two identical periodically driven one-dimensional Su-Schrieffer-Heeger chains.The formation of topological Floquet BICs can be adjusted only by tuning the driving amplitude or frequency,regardless of whether the static system has BICs or not.The interchain bias can only change the localization property of topological Floquet BICs,and a bigger bias can lead to transforming topological Floquet BICs into bound states out of the continuum(BOCs).But it does not change the topological properties of these topological Floquet states.Based on the repulsion effect of edge states,we propose to detect occurrence of topological Floquet BICs and transition point between topological Floquet BICs and BOCs using quantum walk.Our work provided a convenient and realistic approach for the experimental realization and manipulation of BICs in a single-particle quantum system. 展开更多
关键词 generate manipulate topological floquet bound states static system CONTINUUM double SSH chain class systems interchain bias floquet bicsand tunable topological floquet bound states
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Status and Prospect of Weak Radiative Hyperon Decays
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作者 Rui-Xiang Shi Zekun Jia +3 位作者 Li-Sheng Geng Haiping Peng Qiang Zhao Xiaorong Zhou 《Chinese Physics Letters》 2025年第3期44-51,共8页
Weak radiative hyperon decays represent a rich interplay between weak interactions and the internal structure of baryons,offering profound insights into Quantum Chromodynamics and weak interactions.Recent experimental... Weak radiative hyperon decays represent a rich interplay between weak interactions and the internal structure of baryons,offering profound insights into Quantum Chromodynamics and weak interactions.Recent experimental observations,particularly from BESIII,have revealed deviations from theoretical predictions.These deviations could signal new physics or the need for refined theoretical models incorporating intermediate resonance effects.This review discusses recent theoretical advancements and key experimental findings,focusing on recent measurements from BESIII and their implications for strong interactions and baryon structure. 展开更多
关键词 structure refined DECAY
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Spinel inversion-induced magnetic coupling transitions at antiphase boundaries
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作者 Shanshan Chen Ziyi Sun +8 位作者 Qianqian Jin Xuexi Yan Chunyang Gao Ang Tao Yixiao Jiang Tingting Yao Chunlin Chen Xiuliang Ma Hengqiang Ye 《Journal of Materials Science & Technology》 2025年第20期47-55,共9页
Clarifying how spinel inversion affects the magnetic coupling nature at antiphase boundaries(APBs)is crucial for understanding the intriguing magnetic behaviors of spinel ferrites.Here,MgFe_(2)O_(4) films with an inve... Clarifying how spinel inversion affects the magnetic coupling nature at antiphase boundaries(APBs)is crucial for understanding the intriguing magnetic behaviors of spinel ferrites.Here,MgFe_(2)O_(4) films with an inversion coefficient of 2/3 are grown on MgO substrates using pulsed laser deposition(PLD).In-vestigations by state-of-the-art transmission electron microscopy suggest that two types of APBs are formed on the MgFe_(2)O_(4){110}crystal planes.The typeⅠand typeⅡAPBs have the crystal translation of(1/4)a[110]+(1/6)a[1(1)2]and(1/4)a[110]at the boundary,respectively.First-principles calculations reveal that both typeⅠand typeⅡAPBs tend to form antiferromagnetic coupling when the inversion co-efficient in MgFe_(2)O_(4) is zero.When the inversion coefficient rises to 2/3 due to the occupation of Mg^(2+)cations in octahedral sites,the magnetic coupling at the typeⅠAPBs changes to the ferromagnetic cou-pling,while the typeⅡAPBs still remain the antiferromagnetic one.The magnetic coupling modes of the APBs are closely related to the Fe-O-Fe superexchange interaction across the boundaries.Our findings clarify the atomistic mechanism of how spinel inversion affects the magnetic properties of spinel ferrites,which will promote the applications of magnetoelectricity materials with partial inversion. 展开更多
关键词 MgFe_(2)O_(4) Antiphase boundary Cation distribution Magnetic coupling Transmission electron microscopy First-principles calculations
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Variants and Molecular Mechanism of NOTCH1 in Congenital HeartDisease
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作者 Hongqun Xiang Jian Zhuang +1 位作者 Luoning Bao Yan Shi 《Congenital Heart Disease》 2025年第2期245-263,共19页
Congenital heart disease(CHD)is the mnost comman birth defect,with 34%of cases attrib utedto genetic variants.NOTCH1,a multi-domain transmembrane protein,regulates heart developmert bycontrolling the differantiation a... Congenital heart disease(CHD)is the mnost comman birth defect,with 34%of cases attrib utedto genetic variants.NOTCH1,a multi-domain transmembrane protein,regulates heart developmert bycontrolling the differantiation and migration of myocardial mesoderm cells,and different variants are presentin differnt types of CHD.In this review,we aim to provide a detailed description of NOTCH1 structuraldomains and their functions,highlighting NOTCH1 variants in CHD and the molecular mechanisms throughwhich they contribute to CHD occurrence,NOTCH1 has two main domains,the NOTCH extracellulardomain(NBCD)and the NOTCH intracellular domain(NICD).NECD facilitates ligand binding and NICDformation,while the NICD functions as a transcrip tion factor,forming complexes with co-factors in thenucleus to initiate gene transcription.Amnong the NOTCH1 variants associated with CHD occurrence,most are loss-of-function variants.Moreover,most of the variants are located in theEGF-like domain.Themolecular mechanism behind the NOTCH1 variant-associated CHD occurrence appears to be either due to aloss-of-function or missense variant.In the loss-of-function mutations,NOTCH1 haploinsufficiency is notedand directly reduces theNICD production,causing CHD ocaurrence.In the less common case of missensevariant,only a mild NOTCH1 malfuncticn is observed,but insufficient to directly lead to CHD occurrence.However,when a missense variant is combined with a risk factor,such as exposure to an environmentaltoxin,the cumulative effect can lead to CHD.Understanding the genetic and molecular mechanisms linkingNOTCH1 variants to CHD is crucial for improving clinical management and patient quality of life. 展开更多
关键词 NOTCHL congenital heart disease mutation loss-of function variant haploinsuficency
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周期Anderson模型的Green函数方法处理
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作者 朱俊 滕保华 +1 位作者 CHAN F T 邢进华 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第3期493-496,共4页
基于Green函数技术,作者首先分析了切断近似对处理一维对称周期Anderson模型中电子间关联的影响,然后计算了该模型的局域磁矩、杂化能量元和基态能量.计算结果与Blankenkecler等人的MonteCarlo... 基于Green函数技术,作者首先分析了切断近似对处理一维对称周期Anderson模型中电子间关联的影响,然后计算了该模型的局域磁矩、杂化能量元和基态能量.计算结果与Blankenkecler等人的MonteCarlo模拟一致,这表明Green函数方法可以较好地处理周期Anderson模型的基态性质. 展开更多
关键词 ANDERSON模型 基态 格林函数 局域磁矩 电子关联
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^(171)Ta高自旋态能级寿命测量
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作者 张振龙 竺礼华 +13 位作者 吴晓光 王治民 贺创业 王月 孟锐 马瑞刚 崔兴柱 李广生 温书贤 郑勇 A.A.Pastrernak 周宏余 刘运祚 杨春祥 《原子核物理评论》 CAS CSCD 北大核心 2004年第4期336-338,共3页
在中国原子能科学研究院的HI 13串列加速器上通过157Gd(19F,5n)171Ta重离子熔合蒸发反应布居了171Ta的高自旋态,以多普勒移动衰减法的峰形分析法分析了171Tah9/2质子1/2[541]转动带的6条能级的寿命,得到了这6条能级的平均寿命值.
关键词 高自旋态 能级寿命 转动带 峰形 质子 重离子 串列加速器 多普勒 HI 平均寿命
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SABRE雷达及其观测的Pc5地磁脉动Ⅰ.统计分析结果
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作者 田茂 T.K.Yeoman +1 位作者 M.Lester T.B.Jones 《空间科学学报》 CAS CSCD 北大核心 1992年第3期235-240,共6页
本文简要介绍了相干散射雷达SABRE及其观测Pc5地磁脉动的工作原理。1985—1989年观测数据的统计分析结果表明,相位向极传播脉动事件的出现率峰值在当地时间午夜附近,而向赤道传播事件的出现率峰值则在18:00LT左右。文中给出了上述两类... 本文简要介绍了相干散射雷达SABRE及其观测Pc5地磁脉动的工作原理。1985—1989年观测数据的统计分析结果表明,相位向极传播脉动事件的出现率峰值在当地时间午夜附近,而向赤道传播事件的出现率峰值则在18:00LT左右。文中给出了上述两类脉动事件出现率的日变化,与地磁活动的相关,与背景电离层等离子体对流特性的关系等统计分析结果。 展开更多
关键词 相干散射雷达 地磁脉动 观测
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Effects of CRAC Channel on Spatiotemporal Ca2+ Patterns in T Cells
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作者 李丛鑫 陈晓芳 +1 位作者 王鹏业 王渭池 《Chinese Physics Letters》 SCIE CAS CSCD 2010年第2期311-314,共4页
A reaction-diffusion model is built to investigate the temporal and spatial patterns of cytoplasmic Ca2+ dynamics under the effects of Ca2+-release activated Ca2+ (CRAC) channels in T cells. Simulation results sh... A reaction-diffusion model is built to investigate the temporal and spatial patterns of cytoplasmic Ca2+ dynamics under the effects of Ca2+-release activated Ca2+ (CRAC) channels in T cells. Simulation results show a strong dependence of the modulation mode of Ca2+ oscillation and dynamic patterns of Ca2+ wave on the influx rate through the CRAC channel (ksoc). When ksoc is small, cytoplasmic Ca2+ is modulated as a frequency-modulation (FM) signal, whereas it shows an amplitude modulation (AM) mode after ksoc passes through a critical value. The heterogeneity in spatial Ca2+ distribution is mostly arising from the influx through CRAC channels in both FM and AM modes. During each Ca2+ spike, a more sustained cytoplasmic Ca2+ gradient is maintained in the AM mode rather than in the FM mode. 展开更多
关键词 Biological physics
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Holographic Duals of Quark Gluon Plasmas with Unquenched Flavors
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作者 Francesco Bigazzi Aldo Cotrone +2 位作者 Javier Mas Daniel Mayerson Javier Tarrio 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第3期364-386,共23页
We review the construction of gravitational solutions holographically dual to N=1 quiver gauge theories with dynamical flavor multiplets.We focus on the D3-D7 construction and consider the finite temperature,finite qu... We review the construction of gravitational solutions holographically dual to N=1 quiver gauge theories with dynamical flavor multiplets.We focus on the D3-D7 construction and consider the finite temperature,finite quark chemical potential case where there is a charged black hole in the dual solution.Discussed physical outputs of the model include its thermodynamics (with susceptibilities) and general hydrodynamic properties. 展开更多
关键词 AdS/CFT correspondence quark-gluon plasma flavor physics finite baryon density
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Li-Si合金中间相作为锂离子电池负极材料的研究(英文) 被引量:9
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作者 侯贤华 胡社军 +1 位作者 汝强 张志文 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2010年第12期2079-2083,共5页
采用基于密度泛函理论的第一性原理平面波赝势方法计算了Li-Si各种合金相的物理性质和电化学性能。结果表明:除了在反应过程中生成传统的固态电解质SEI膜之外,形成的Li12Si7合金相也是部分导致首次不可逆容量损失的重要原因。另外,采用... 采用基于密度泛函理论的第一性原理平面波赝势方法计算了Li-Si各种合金相的物理性质和电化学性能。结果表明:除了在反应过程中生成传统的固态电解质SEI膜之外,形成的Li12Si7合金相也是部分导致首次不可逆容量损失的重要原因。另外,采用射频磁控溅射制备了纯Si薄膜电极,并运用XRD、循环伏安CV、恒流充放电CC表征和测试了材料的结构和电化学性能,结果表明首次不可逆容量损失非常大,无定型结构能有效抑制体积膨胀和改善循环性能。 展开更多
关键词 合金相 中间相 锂离子电池负极材料 Materials for 首次不可逆容量损失 electrochemical performance density functional theory 电化学性能 amorphous structure solid electrolyte constant current radio frequency results film electrode 密度泛函理论 磁控溅射制备 恒流充放电 第一性原理 the growth method of
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自蔓延高温合成多孔NiTi合金孔隙的SVR预测 被引量:4
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作者 蔡从中 温玉锋 +2 位作者 裴军芳 朱星键 王桂莲 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2010年第10期1719-1722,共4页
根据自蔓延高温合成法(SHS)制备多孔NiTi合金孔隙试验所获得的实测数据集,应用基于粒子群算法(PSO)寻优的支持向量回归(SVR)方法,建立不同反应参数(温度,粒度和压坯密度)下合成的多孔NiTi合金孔隙的SVR预测模型,并与基于误差反向传播神... 根据自蔓延高温合成法(SHS)制备多孔NiTi合金孔隙试验所获得的实测数据集,应用基于粒子群算法(PSO)寻优的支持向量回归(SVR)方法,建立不同反应参数(温度,粒度和压坯密度)下合成的多孔NiTi合金孔隙的SVR预测模型,并与基于误差反向传播神经网络(BPNN)回归模型的预测结果进行比较。结果表明:在相同的训练与测试样本集下所获的SVR预测结果的平均绝对百分误差(MAPE)比BPNN预测模型的要小,其预测精度更高,预测效果更好;SVR-LOOCV预测的MAPE也比BPNN略小,且其预测结果的相关系数达到了0.999。因此,该方法是一种预测SHS法制备多孔NiTi合金孔隙的有效方法,可为SHS合成多孔NiTi提供理论指导。 展开更多
关键词 自蔓延高温合成法 多孔 NITI合金 孔隙 SVR 预测结果 Synthesis 误差反向传播神经网络 预测模型 支持向量回归 方法 训练与测试 粒子群算法 SHS合成 制备 预测效果 预测精度 压坯密度 相关系数 理论指导
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SYNTHESIS AND PROPERTIES OF NOVEL POLY(IMINO KETONE)S AS HIGH-PERFORMANCE POLYMERS 被引量:11
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作者 Chang, Guan-jun Luo, Xuan +1 位作者 Zhang, Lin Lin, Run-xiong 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第1期55-61,共7页
Di(4-bromophenyl)ketone and various aromatic diamines as the monomers,a series of novel poly(imino ketone)s (PIKs)have been synthesized via palladium-catalyzed aryl amination,which is Hartwig-Buchwald polycondensation... Di(4-bromophenyl)ketone and various aromatic diamines as the monomers,a series of novel poly(imino ketone)s (PIKs)have been synthesized via palladium-catalyzed aryl amination,which is Hartwig-Buchwald polycondensation reaction.The structures of PIKs are characterized by means of elemental analysis,FT-IR,~1H-NMR and UV-Vis spectroscopy. The results show a good agreement with the proposed structure.The general properties of PIKs are studied by DSC,TG and wide-angle X-ray diffraction,the solubility behavior is... 展开更多
关键词 Di(4-bromophenyl)ketone Aromatic diamines Palladium-catalyzed aryl amination High-performance Poly(imino ketone)
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Prevalence and risk factors of fatty liver disease in Chengdu,Southwest China 被引量:22
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作者 Li, Hong Wang, You-Juan +6 位作者 Tan, Ke Zeng, Li Liu, Li Liu, Feng-Jun Zhou, Tao-You Chen, En-Qiang Tang, Hong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2009年第4期377-382,共6页
BACKGROUND: Fatty liver disease (FLD) is increasingly recognized as one of the most common chronic liver diseases in China. This study aimed to investigate the prevalence and risk factors of FLD in Chengdu, Southwest ... BACKGROUND: Fatty liver disease (FLD) is increasingly recognized as one of the most common chronic liver diseases in China. This study aimed to investigate the prevalence and risk factors of FLD in Chengdu, Southwest China, and to provide a relevant basis for the prevention and intervention of FLD. METHODS: Altogether 9094 subjects (4721 men and 4373 women) of over 18 years old who had received a medical checkup in the West China Hospital of Sichuan University between January and December 2007 were evaluated for FLD. FLD was diagnosed by ultrasonography. Body mass index (BMI), height, body weight, blood pressure, fasting plasma glucose (FPG), triglycerides (TG), total cholesterol (TCh), alanine aminotransferase (ALT), hepatitis B surface antigen (HBsAg), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were measured using routine laboratory methods. RESULTS: The overall prevalence of FLD was 12.5%, which was more than 3-fold higher in males than in females 2 (18.9% vs. 5.7%, chi(2) =359.624, P<0.001). The prevalence increased with age in females and males of less than 50 years. The prevalence of alcoholic, suspected alcoholic, and non-alcoholic FLD was 2.6%, 3.6%, and 6.3%, respectively. Multiple logistic regression analyses showed that 10 factors (male sex, age, BMI, FPG, hypertension, TG, TCh, HDL-C, LDL-C, and ALT abnormalities) were closely related to FLD. In heavy drinkers, obesity increased the risk of FLD by 23.78-fold (95% CI, 10.22-55.33), but heavy drinking was only associated with a 2-fold (95% CI, 1.50-2.66) increased risk in obese subjects. CONCLUSIONS: The prevalence of FLD among a health-checkup population in Chengdu, Southwest China was lower than the published for other areas of China. FLD in Chengdu adults was found to be closely associated with sex, age, BMI, and other metabolic syndrome features. 展开更多
关键词 fatty liver PREVALENCE risk factors OBESITY ALCOHOLS
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LsrR-binding site recognition and regulatory characteristics in Escherichia coli AI-2 quorum sensing 被引量:13
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作者 Ting Xue Liping Zhao +2 位作者 Haipeng Sun Xianxuan Zhou Baolin Sun 《Cell Research》 SCIE CAS CSCD 2009年第11期1258-1268,共11页
In quorum sensing (QS) process, bacteria regulate gene expression by utilizing small signaling molecules called autoinducers in response to a variety of environmental cues. Autoinducer 2 (AI-2), a QS signaling mol... In quorum sensing (QS) process, bacteria regulate gene expression by utilizing small signaling molecules called autoinducers in response to a variety of environmental cues. Autoinducer 2 (AI-2), a QS signaling molecule proposed to be involved in interspecies communication, is produced by many species of gram-negative and gram-positive bacteria. In Escherichia coil and Salmonella typhimurium, the extracellular AI-2 is imported into the cell by a transporter encoded by the lsr operon. Upstream of the lsr operon, there is a divergently transcribed gene encoding LsrR, which was reported previously to repress the transcription of the lsr operon and itself. Here, we have demonstrated for the first time that LsrR represses the transcription of the lsr operon and itself by directly binding to their promoters using gel shift and DNase I footprinting assays. The β-galactosidase reporter assays further suggest that two motifs in both the lsrR and lsrA promoter regions are crucial for the LsrR binding. Furthermore, in agreement with the conclusion that phosphorylated AI-2 can relieve the repression of LsrR in previous studies, our data show that phospho- AI-2 renders LsrR unable to bind to its own promoter in vitro. 展开更多
关键词 quorum sensing LSRR AI-2
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Glass-forming ability and crystallization of Mg-Ni amorphous alloys with Y addition 被引量:8
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作者 Liu Liyan Teng Xinying +1 位作者 Wang Yongjie Liu Teng 《Rare Metals》 SCIE EI CAS CSCD 2012年第3期244-249,共6页
Mg86.33Ni13.67-xYx(x=0, 1, 3, 6, 10) amorphous alloys were obtained by single-roller melt-spinning technique and the effect of Y addition on the glass forming ability(GFA), crystallization and micro-hardness of Mg-Ni ... Mg86.33Ni13.67-xYx(x=0, 1, 3, 6, 10) amorphous alloys were obtained by single-roller melt-spinning technique and the effect of Y addition on the glass forming ability(GFA), crystallization and micro-hardness of Mg-Ni alloys were studied. The results show that the GFA of Mg86.33Ni13.67-xYx(x=0, 1, 3, 6, 10) is improved successfully with the Y addition. The highest GFA appeares at x=6, while the reduced glass transition temperature (Trg) is 0.5225 and the supercooled liquid region(ΔTx) is 42.06 K; the position of the main diffraction halo is different for the alloys, and the maximum of the main diffraction halo of alloys with x=0, 1, 3 corresponds to the main peaks of a metastable fcc-Mg6Ni or fcc-Mg6Ni + Ni-Y intermetallic phases, and for the alloys with x=6, 10, it corresponds to Mg-Y and Ni-Y intermetallic phases; the micro-hardness of the alloys is improved with Y additions, and the highest micro-hardness is obtained at x=6 at.%, which is 960 MPa. 展开更多
关键词 Mg-based amorphous alloy glass forming ability CRYSTALLIZATION micro-hardness
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