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Homo-& Heteroclinic Orbits in Conservative Systems with 3-wells Potential 被引量:1
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作者 黄明游 李松涛 +1 位作者 张凯 李勇 《Northeastern Mathematical Journal》 CSCD 2002年第4期287-290,共4页
Consider the following 2×2 nonlinear system:where f(u): R→R is a, smooth function. Setwhere F’(u)= f(u). Then (1) can be rewritten as an equivalent Hamiltonian system:
关键词 conservative systems 3-wells potential homoclinic and heteroclinicorbits
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Forensic Study on Objective Evaluation of Visual Acuity of Ametropia with the Event-related Potential P3
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作者 Fu-quan JIA Fang-liang LUO +3 位作者 Yan-he XIONG Long-long CHENG Zhi-qiang DANG Ji-hui LIU 《Current Medical Science》 SCIE CAS 2023年第3期609-614,共6页
Objective In this study,we aimed to assess the characteristics of the P3 component from an event-related potential(ERP)that was induced by visual acuity(VA)processing.Furthermore,we sought to provide electrophysiologi... Objective In this study,we aimed to assess the characteristics of the P3 component from an event-related potential(ERP)that was induced by visual acuity(VA)processing.Furthermore,we sought to provide electrophysiological evidence for the objective evaluation of VA.Methods We recruited 32 participants with myopia-related ametropia.They reported no other ocular diseases and had an uncorrected VA of 4.0 in both eyes.We used the block letter“E”at different visual angles and orientations as the graphic stimuli.The oddball paradigm,consisting of 4 modules,was used for ERP analysis.The standard stimuli of each module were identical,with a visual angle of 1°15′.The visual angles of the target stimuli were 1°15′,55′,24′,and 15′.The VA test was performed on each eye separately for all participants,and all characteristics of the P3 component were analyzed.Results There was no significant difference in the P3 peak letencies between the target stimulation angle 1°15′group and the 55′group,or between the target stimulation angle 24′group and the 15′group.There was a significant difference in the P3 peak letencies between the target stimulation angle 1°15′group and the 24′group as well as the 15′group.There was a significant difference in the P3 peak letencies between the target stimulation angle 55′group and the 24′group as well as the 15′group.No significant differences were observed in the P3 amplitude between modules.Conclusion In the oddball paradigm,P3 elicitation indicated a cognitive response to the target stimuli.These data showed that the characteristics of P3 can be used as an objective evaluation of VA. 展开更多
关键词 event-related potential P3 visual acuity forensic medicine AMPLITUDE
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Effect of potential difference between nano-Al_(2)O_(3)whisker and Mg matrix on the dispersion of Mg composites
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作者 Xiaoying Qian Hong Yang +6 位作者 Chunfeng Hu Ying Zeng Yuanding Huang Xin Shang Yangjie Wan Bin Jiang Qingguo Feng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第1期104-111,共8页
The potential difference between positive and negative ions was utilized to improve the homogenized dispersion of nanoscale Al_(2)O_(3) whiskers in Mg matrix composites.The Mg powders were decorated with sodium dodecy... The potential difference between positive and negative ions was utilized to improve the homogenized dispersion of nanoscale Al_(2)O_(3) whiskers in Mg matrix composites.The Mg powders were decorated with sodium dodecylbenzene sulfonate(C_(18)H_(29)NaO_(3)S,SDBS)and were introduced to the cathode group on their surface.The Al_(2)O_(3) whiskers were modified by the cetyl trimethyl ammonium bromide(C_(19)H_(42)BrN,CTAB)and were featured in the anode group.The suitable contents of CTAB and SDBS,the application atmosphere,and the type of solvents were investigated.Dispersion results showed that adding 2wt%SDBS into Mg powders and adding 2wt%CTAB into Al_(2)O_(3) whiskers pro-moted the formation of more uniformly mixed composite powders,compared to those of conventional ball milling via scanning electron micro-scopy(SEM)analysis.Meanwhile,the calculated results derived from first-principle calculations also demonstrated the stronger cohesion between Al_(2)O_(3) whisker reinforcements and Mg matrix than undecorated composite powders.After preparation by powder metallurgy,the mor-phology,grain size,hardness,and standard deviation coefficient of composites were analyzed to evaluate the dispersed efficiency.The results indicated that the modification of homogenized dispersed Al_(2)O_(3) whiskers in composites contributed to the refinement of 26%in grain size and the improvement of 20%in hardness compared with pure Mg,and the reduction of 32.5%in the standard deviation coefficient of hardness compared with the ball-milling sample. 展开更多
关键词 magnesium-based composites Al_(2)O_(3)whiskers potential difference DISPERSION
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基于NGF/PI3K/TRPV1信号通路探究参苓白术散对腹泻型肠易激综合征小鼠的干预机制
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作者 朱卫 翦闽涛 曾婷婷 《现代消化及介入诊疗》 2024年第5期547-551,共5页
目的研究基于神经生长因子/磷脂酰肌醇3-激酶/瞬时受体电位香草酸受体1(NGF/PI3K/TRPV1)信号通路探究参苓白术散对腹泻型肠易激综合征小鼠的干预机制。方法选取40只SPF级SD雄性大鼠,其中空白组10只,模型组13只、研究1组7只、研究2组9只... 目的研究基于神经生长因子/磷脂酰肌醇3-激酶/瞬时受体电位香草酸受体1(NGF/PI3K/TRPV1)信号通路探究参苓白术散对腹泻型肠易激综合征小鼠的干预机制。方法选取40只SPF级SD雄性大鼠,其中空白组10只,模型组13只、研究1组7只、研究2组9只。对照组、模型组只进行生理盐水灌胃,不做其他任何处理。研究1组给予匹维溴铵片20mg/kg水溶液进行灌胃,研究2组给予参苓白术散4g/kg进行灌胃。评估Bristol评分情况;分析脾脏系数、胸腺系数情况;检测IgA、IgG、IgM、IL-1β、IL-6、TNF-α表达水平及NGF/PI3K/TRPV1蛋白表达情况。结果相比于空白组,模型组、研究1组、研究2组Bristol评分、脾脏系数、胸腺系数、IgA、IgG、IgM、IL-1β、IL-6、TNF-α水平及NGF、PI3K、TRPV1蛋白表达均上升(P<0.05);相比于模型组、研究1组,研究2组Bristol评分、脾脏系数、胸腺系数、IgA、IgG、IgM、IL-1β、IL-6、TNF-α水平及NGF、PI3K、TRPV1蛋白表达均下降(P<0.05)。结论参苓白术散抑制NGF/PI3K/TRPV1通路,改善大鼠胃肠功能及大便状态,减轻炎症反应,提高免疫功能稳态情况,干预效果显著。 展开更多
关键词 参苓白术散 神经生长因子/磷脂酰肌醇3-激酶/瞬时受体电位香草酸受体1 腹泻型肠易激综合征 炎症反应
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The Measurement of Membrane Potential and NO3 Activity in Root Cells Using Ion-Selective Microelectrodes 被引量:3
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作者 FANXiao-rong AnthonyJMiller SHENQi-rong 《Agricultural Sciences in China》 CAS CSCD 2003年第10期1097-1101,共5页
Remobilisation of nitrate in plants, especially in vacuole of plant, is mostly related to the qua- lity of agricultural products and the high nitrogen use efficiency in plants. Ion-selective microelectrodes offer a n... Remobilisation of nitrate in plants, especially in vacuole of plant, is mostly related to the qua- lity of agricultural products and the high nitrogen use efficiency in plants. Ion-selective microelectrodes offer a non-destructive and non-interruptive method to measure NO 3 gradients and electric potential differences across both the plasma membrane and tonoplast. Thus, a double-barrelled microelectrode backfilled with a membrane sensor for NO 3 embedded in poly vinyl chloride (PVC) can record the NO 3 activity in cytoplasm and vacuole of a cell. This paper presented how to make this kind of microelectrode and how to do the intracellular measurements on intact plants. Our result showed that nitrate activity was about 2.7 mmol L 1 in cytoplasm while 70 mmol L 1 in vacuole, which implicated that vacuole was a pool of nitrate in plants. 展开更多
关键词 Ion-selective microelectrodes Membrane potential NO 3 activity
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The transient receptor potential melastatin 2:a new therapeutical target for Parkinson's disease? 被引量:2
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作者 Ana Flávia F.Ferreira Luiz Roberto G.Britto 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第8期1652-1656,共5页
The transient receptor potential melastatin 2 is a calcium-permeable cation channel member of the TRP family. Also known as an oxidative stress-activated channel, the transient receptor potential melastatin 2 gating m... The transient receptor potential melastatin 2 is a calcium-permeable cation channel member of the TRP family. Also known as an oxidative stress-activated channel, the transient receptor potential melastatin 2 gating mechanism is dependent on reactive oxygen species. In pathological conditions, transient receptor potential melastatin 2 is overactivated, leading to a Ca~(2+) influx that alters cell homeostasis and promotes cell death. The role of transient receptor potential melastatin 2 in neurodegenerative diseases, including Alzheimer's disease and ischemia, has already been described and reviewed. However, data on transient receptor potential melastatin 2 involvement in Parkinson's disease pathology has emerged only in recent years and the issue lacks review studies that focus specifically on this topic. The present review aims to elucidate the role of the transient receptor potential melastatin 2 channel in Parkinson's disease by reviewing, summarizing, and discussing the in vitro, in vivo, and human studies published until August 2022. Here we describe fourteen studies that evaluated the transient receptor potential melastatin 2 channel in Parkinson's disease. The Parkinson's disease model used, transient receptor potential melastatin 2 antagonist and genetic approaches, and the main outcomes reported were discussed. The studies described transient receptor potential melastatin 2 activation and enhanced expression in different Parkinson's disease models. They also evidenced protective and restorative effects when using transient receptor potential melastatin 2 antagonists, knockout, or silencing. This review provides a literature overview and suggests where there is a need for more research. As a perspective point, this review shows evidence that supports transient receptor potential melastatin 2 as a pharmacological target for Parkinson's disease in the future. 展开更多
关键词 1-methyl-4-phenyl-1 2 3 6-tetrahydropyridine(MPTP) 1-methyl-4-phenylpyridinium(MPP+) 6-HYDROXYDOPAMINE AG490 CLOTRIMAZOLE flufenamic acid N-(p-amylcinnamoyl)anthranilic acid Parkinson's disease poly-ADPR polymerase type 1(PARP1) ROTENONE PARAQUAT transient receptor potential melastatin 2(TRPM2)
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2019~2022年华北平原典型地区不同污染等级和污染持续时间下的O_(3)污染规律及来源
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作者 钱昱先 王刚 +2 位作者 孟庆晓 刘赛 王永强 《中国环境科学》 EI CAS CSCD 北大核心 2024年第7期3581-3591,共11页
选取地势复杂的日照市莒县为研究区域,基于2019~2022年莒县省控站点的O_(3)监测数据,按照不同O_(3)污染等级与不同O_(3)污染持续时间对莒县的O_(3)污染天进行分类,探究其污染规律,并采用后向轨迹模型(HYSPLIT)、潜在源分析(PSCF)和浓度... 选取地势复杂的日照市莒县为研究区域,基于2019~2022年莒县省控站点的O_(3)监测数据,按照不同O_(3)污染等级与不同O_(3)污染持续时间对莒县的O_(3)污染天进行分类,探究其污染规律,并采用后向轨迹模型(HYSPLIT)、潜在源分析(PSCF)和浓度权重轨迹分析法(CWT)识别不同O_(3)污染事件下的O_(3)来源.结果显示:2019~2021年莒县O_(3)轻度污染天数由72d下降到38d,2022年反弹,而中度污染天数变化不大;轻微污染天在轻度污染天中占比较高(21.4%~39.5%),表明轻度污染天的改善空间很大,强化轻微污染天管控措施,将有利于将轻度污染天转化为优良天,提高当地空气质量优良率.O_(3)污染过程持续时间越长(如≥3d),污染发生的频率越低,而O_(3)浓度随污染持续时间的增加而升高.HYSPLIT模拟结果显示不同O_(3)污染等级和不同O_(3)污染持续时间的气团轨迹均以莒县东南方向为主,且以中、短距离传输为主,其中中度污染期间来自东南地区的O_(3)-8h-90%浓度最高[(250.0±65.9)µg/m^(3)].PSCF和CWT结果显示,O_(3)潜在源区主要分布在莒县东南方向,长江三角洲地区是莒县O_(3)污染的主要的潜在源区.研究结果对于指导莒县及周边区域的大气污染联防联控具有重要意义. 展开更多
关键词 臭氧 污染等级 污染持续时间 后向轨迹 潜在源区
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3'-Deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome 被引量:1
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作者 Yize Qi Yao Zhou +8 位作者 Jiyang Li Fangyuan Zhu Gengni Guo Can Wang Man Yu Yijie Wang Tengfei Ma Shanwu Feng Li Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2270-2280,共11页
Methamphetamine addiction is a brain disorder characterized by persistent drug-seeking behavior, which has been linked with aberrant synaptic plasticity. An increasing body of evidence suggests that aberrant synaptic ... Methamphetamine addiction is a brain disorder characterized by persistent drug-seeking behavior, which has been linked with aberrant synaptic plasticity. An increasing body of evidence suggests that aberrant synaptic plasticity is associated with the activation of the NOD-like receptor family pyrin domain containing-3(NLRP3) inflammasome. 3′-Deoxyadenosin, an active component of the Chinese fungus Cordyceps militaris, has strong anti-inflammatory effects. However, whether 3′-deoxyadenosin attenuates methamphetamine-induced aberrant synaptic plasticity via an NLRP3-mediated inflammatory mechanism remains unclear. We first observed that 3′-deoxyadenosin attenuated conditioned place preference scores in methamphetamine-treated mice and decreased the expression of c-fos in hippocampal neurons. Furthermore, we found that 3′-deoxyadenosin reduced the aberrant potentiation of glutamatergic transmission and restored the methamphetamine-induced impairment of synaptic plasticity. We also found that 3′-deoxyadenosin decreased the expression of NLRP3 and neuronal injury. Importantly, a direct NLRP3 deficiency reduced methamphetamine-induced seeking behavior, attenuated the impaired synaptic plasticity, and prevented neuronal damage. Finally, NLRP3 activation reversed the effect of 3′-deoxyadenosin on behavior and synaptic plasticity, suggesting that the anti-neuroinflammatory mechanism of 3′-deoxyadenosin on aberrant synaptic plasticity reduces methamphetamine-induced seeking behavior. Taken together, 3′-deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome. 展开更多
关键词 3′-deoxyadenosin hippocampus long-term potentiation METHAMPHETAMINE NOD-like receptor family pyrin domain containing-3(NLRP3)inflammasome synaptic plasticity
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六氟钽酸氨拓扑转变制备低深能级缺陷Ta_(3)N_(5)光阳极实现超低偏压光电化学分解水
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作者 徐伟 甄超 +7 位作者 朱华泽 姚婷婷 邱建航 梁艳 白朔 陈春林 成会明 刘岗 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第6期144-153,共10页
Ta_(3)N_(5)是一种具有2.1 eV直接带隙的n型半导体,其带隙跨越水的氧化还原电位.此外,Ta_(3)N_(5)的理论太阳能制氢效率(STH)高达15.9%,超过商业化应用的效率门槛(10%),是一种理想的光电化学分解水制氢光阳极材料.采用Ta2O5作为前驱体,... Ta_(3)N_(5)是一种具有2.1 eV直接带隙的n型半导体,其带隙跨越水的氧化还原电位.此外,Ta_(3)N_(5)的理论太阳能制氢效率(STH)高达15.9%,超过商业化应用的效率门槛(10%),是一种理想的光电化学分解水制氢光阳极材料.采用Ta2O5作为前驱体,在氨气气氛下高温氮化制备Ta_(3)N_(5)是一个由表及里的非均相氮化过程,该过程会产生大量的低价钽和氮空位等本征深能级缺陷,导致费米能级钉扎效应的产生,从而使得光生电压显著降低和光电流起始电位较高.因此,开发能够进行体相均相氮化的前驱体,以抑制Ta_(3)N_(5)深能级缺陷的产生,具有重要意义.本文采用气相溶剂热法,在钽箔上制备了一种六氟钽酸氨((NH_(4))_(2)Ta_(2)O_(3)F_(6))化合物,并以其多面体锥阵列薄膜作为前驱体,通过可控的氮化过程将前驱体结构拓扑转变为低深能级缺陷含量的Ta_(3)N_(5)多孔阵列薄膜.在高温氮化过程中,(NH_(4))_(2)Ta_(2)O_(3)F_(6)会释放含氮、氢和氟的气体小分子并形成贯穿体相的多孔通道,有利于氨气及氮化过程中产生的其他小分子物质的渗透,促进体相均匀氮化过程,避免生成大量的本征深能级缺陷.同时,(NH_(4))_(2)Ta_(2)O_(3)F_(6)中的高电负性氟离子可以减弱Ta–O键,进一步促进氮化反应.扫描电镜和透射电镜(TEM)结果表明,制备的(NH_(4))_(2)Ta_(2)O_(3)F_(6)是具有实心结构的多面体锥阵列薄膜,而拓扑转变所得的Ta_(3)N_(5)多面体锥薄膜具有多孔结构.X射线光电子能谱(XPS)、紫外-可见漫反射光谱和稳态/瞬态光电压谱表征结果表明,通过(NH_(4))_(2)Ta_(2)O_(3)F_(6)拓扑转变制备Ta_(3)N_(5)可有效抑制Ta_(3)N_(5)薄膜中深能级缺陷的形成.采用两种产氧反应助催化剂依次修饰后,XPS和TEM结果显示出助催化剂的双壳层结构与化学组成.光电化学分解水测试结果表明,所制得的Ta_(3)N_(5)光阳极在AM1.5G模拟太阳光的照射下,可展现出0.2 V_(RHE)(vs.RHE)的极低光电流起始电位,且在1.23 V_(RHE)时的光电流密度可达3.28 mA cm^(–2),经过连续5 h的稳定性测试,仍能保持初始值的85%.此外,稳定性测试前后助催化剂的XPS和TEM结果表明,Ta_(3)N_(5)光阳极光电流下降的原因可能是产氧助催化剂中硼物种的消耗.而通过减小(NH_(4))_(2)Ta_(2)O_(3)F_(6)多面体锥前驱体的尺寸,可以进一步减少Ta_(3)N_(5)薄膜中的本征深能级缺陷的含量,修饰助催化剂后可在0 V_(RHE)下展现出光电催化水氧化活性.综上所述,通过(NH_(4))_(2)Ta_(2)O_(3)F_(6)新型前驱体拓扑转变制备了低深能级缺陷含量的Ta_(3)N_(5)光阳极,表现出极低的光电流起始电位,为构建无偏压下自发全分解水的低深能级缺陷浓度的Ta_(3)N_(5)光电极提供了一种新途径,该方法也可拓展至其他过渡金属氮化物的可控制备与缺陷调控. 展开更多
关键词 (NH_(4))_(2)Ta_(2)O_(3)F_(6) 拓扑转变 低缺陷Ta3N5 起始电位 光电化学分解水
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Numerical simulation of standing wave with 3D predictor-corrector finite difference method for potential flow equations 被引量:3
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作者 罗志强 陈志敏 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第8期931-944,共14页
A three-dimensional (3D) predictor-corrector finite difference method for standing wave is developed. It is applied to solve the 3D nonlinear potential flow equa- tions with a free surface. The 3D irregular tank is ... A three-dimensional (3D) predictor-corrector finite difference method for standing wave is developed. It is applied to solve the 3D nonlinear potential flow equa- tions with a free surface. The 3D irregular tank is mapped onto a fixed cubic tank through the proper coordinate transform schemes. The cubic tank is distributed by the staggered meshgrid, and the staggered meshgrid is used to denote the variables of the flow field. The predictor-corrector finite difference method is given to develop the difference equa- tions of the dynamic boundary equation and kinematic boundary equation. Experimental results show that, using the finite difference method of the predictor-corrector scheme, the numerical solutions agree well with the published results. The wave profiles of the standing wave with different amplitudes and wave lengths are studied. The numerical solutions are also analyzed and presented graphically. 展开更多
关键词 three-dimensional 3D) nonlinear potential flow equation predictor-corrector finite difference method staggered grid nested iterative method 3D sloshing
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Symmetry analysis and explicit solutions of the (3+1)-dimensional baroclinic potential vorticity equation 被引量:1
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作者 胡晓瑞 陈勇 黄菲 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期35-45,共11页
This paper investigates an important high-dimensional model in the atmospheric and oceanic dynamics-(3+1)- dimensional nonlinear baroclinic potential vorticity equation by the classical Lie group method. Its symmet... This paper investigates an important high-dimensional model in the atmospheric and oceanic dynamics-(3+1)- dimensional nonlinear baroclinic potential vorticity equation by the classical Lie group method. Its symmetry algebra, symmetry group and group-invariant solutions are analysed. Otherwise, some exact explicit solutions are obtained from the corresponding (2+1)-dimensional equation, the inviscid barotropic nondivergent vorticy equation. To show the properties and characters of these solutions, some plots as well as their possible physical meanings of the atmospheric circulation are given out. 展开更多
关键词 3+1)-dimensional nonlinear baroclinic potential vorticity equation symmetry group group-invariant solution explicit solution
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Statistical potentials for 3D structure evaluation:From proteins to RNAs 被引量:1
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作者 谭雅岚 封晨洁 +2 位作者 王勋勋 张文炳 谭志杰 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第2期103-115,共13页
Structure evaluation is critical to in silico 3-dimensional structure predictions for biomacromolecules such as proteins and RNAs.For proteins,structure evaluation has been paid attention over three decades along with... Structure evaluation is critical to in silico 3-dimensional structure predictions for biomacromolecules such as proteins and RNAs.For proteins,structure evaluation has been paid attention over three decades along with protein folding problem,and statistical potentials have been shown to be effective and efficient in protein structure prediction and evaluation.In recent two decades,RNA folding problem has attracted much attention and several statistical potentials have been developed for RNA structure evaluation,partially with the aid of the progress in protein structure prediction.In this review,we will firstly give a brief overview on the existing statistical potentials for protein structure evaluation.Afterwards,we will introduce the recently developed statistical potentials for RNA structure evaluation.Finally,we will emphasize the perspective on developing new statistical potentials for RNAs in the near future. 展开更多
关键词 statistical potential 3-dimensional structure evaluation RNA PROTEIN
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The theoretical study on the potential energy curve for X^3△ state of TiO molecule 被引量:1
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作者 徐国亮 夏要争 +2 位作者 贾光瑞 刘玉芳 张现周 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期309-312,共4页
This paper applies the density functional theory method to optimise the structure for X3A state of TiO molecule with the basis sets 6-31G, 6-31++G and 6-311G^**. Comparing the attained results with the experiments... This paper applies the density functional theory method to optimise the structure for X3A state of TiO molecule with the basis sets 6-31G, 6-31++G and 6-311G^**. Comparing the attained results with the experiments, it obtains the conclusion that the basis set 6-31++G is most suitable for the optimal structure calculations of X3A state of TiO molecule. The whole potential energy curve for the electronic state is further scanned by using B3P86/6-31++G method for the ground state, then it uses a least square fitted to Murrell-Sorbie functions, at last it calculates the spectroscopic constants and force constants, which are in better agreement with the experimental data. 展开更多
关键词 B3P86 TIO potential energy function spectroscopic constants
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Potential Barrier Behavior of BaTiO3-(Bi0.5Na0.5)TiO3 Positive Temperature Coefficient of Resistivity Ceramic 被引量:1
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作者 冷森林 石维 +1 位作者 李国荣 郑嘹赢 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期90-93,共4页
High-Curie-temperature (Tc) lead-free Y-doped 90 mol%BaTiO3-1O mol%(Bi0.5Na0.5 ) TiO3 ceramic with positive temperature coefficient of resistivity (PTCR) is prepared by the conventional solid state reaction in n... High-Curie-temperature (Tc) lead-free Y-doped 90 mol%BaTiO3-1O mol%(Bi0.5Na0.5 ) TiO3 ceramic with positive temperature coefficient of resistivity (PTCR) is prepared by the conventional solid state reaction in nitrogen atmosphere. The PTCR ceramic exhibits a room-temperature resistivity (p25) of ~500Ω.cm and a high PTCR effect (maximum resistivity (ρmax)/minimum resistivity (ρmin)) of ~4.5 orders of magnitude. A capacitance- voltage approach is first employed to calculate the potential barrier ( Ф ) of the grain boundary of PTCR ceramic above Tc. It is found that the potential barrier changes from 0.17 to 0.77eV as the temperature increases from 180 to 220℃, which is very close to the predictions of the Heywang-Jonker model, suggesting that the capacitance-voltage method is valid to estimate the potential barrier of PTCR thermistor ceramics. 展开更多
关键词 potential Barrier Behavior of BaTiO3 NA Bi
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New Exact Solutions and Conservation Laws to (3+1)-Dimensional Potential-YTSF Equation 被引量:10
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作者 ZHANG Li-Hua LIU Xi-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期487-492,共6页
用修改 CK 的直接方法,我们造在新答案和旧的和 Snd 一些之间的关系的新准确答案(3+1 ) 维的 potential-YTSFequation。基于不变的组理论,谎言点对称组和谎言对称(3+1 ) 维的 potential-YTSF 方程被获得。我们也与给定的谎言对称得到... 用修改 CK 的直接方法,我们造在新答案和旧的和 Snd 一些之间的关系的新准确答案(3+1 ) 维的 potential-YTSFequation。基于不变的组理论,谎言点对称组和谎言对称(3+1 ) 维的 potential-YTSF 方程被获得。我们也与给定的谎言对称得到方程的能量守恒定律。 展开更多
关键词 精确解法 守恒法则 对称群 三维空间势能-YTSF方程
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The expression,function,and coding potential of circular RNA circEDC3 in chicken skeletal muscle development
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作者 WEI Yuan-hang ZHAO Xi-yu +6 位作者 SHEN Xiao-xu YE Lin ZHANG Yao WANG Yan LI Di-yan ZHU Qing YIN Hua-dong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第5期1444-1456,共13页
As an emerging class of non-coding transcripts,circular RNAs(circRNAs)are proved to participate in the complex process of myogenesis in diverse species.A previous study has identified circular RNA EDC3(circEDC3)as a t... As an emerging class of non-coding transcripts,circular RNAs(circRNAs)are proved to participate in the complex process of myogenesis in diverse species.A previous study has identified circular RNA EDC3(circEDC3)as a typical covalently closed circular RNA abundant in chicken skeletal muscle.This study found that circEDC3 is a conservative circular RNA and performed functional analysis to investigate the role of circEDC3 in chicken muscle growth.The results indicated that circEDC3 could inhibit(P<0.05)chicken skeletal muscle satellite cells(SMSCs)proliferation and differentiation but had no significant influence on SMSCs apoptosis.Additionally,bioinformatics analysis showed that circEDC3 had promising coding potential.The open reading frames(ORF)were found in circEDC3 in this study.Furthermore,this study predicted that circEDC3 had internal ribosome entry sites(IRES)and N6-methyladenosine(m6A)motifs in different species,implying that circEDC3 might be translatable.This study revealed that circEDC3 might be a negative regulator in chicken muscle development and suggested it has protein-coding potential in different species. 展开更多
关键词 circEDC3 CHICKEN SMSCs MYOGENESIS coding potential
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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats
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作者 Pengfei Wang Yuewei Bi +6 位作者 Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1164-1177,共14页
Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Cu... Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia. 展开更多
关键词 aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials NEUROMODULATION Parkinson’s disease primary motor cortex
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Transient Receptor Potential Melastatin 3 and Intracellular Calcium in Natural Killer Cells in Multiple Sclerosis
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作者 Laura Clarke Simon L. Broadley +4 位作者 Thao Nguyen Samantha Johnston Natalie Eaton Donald Staines Sonya Marshall-Gradisnik 《International Journal of Clinical Medicine》 2018年第7期541-565,共25页
Background: Natural killer (NK) cell phenotypes have reported to be implicated in the pathomechanism of Multiple Sclerosis (MS). Several investigators have observed reduced peripheral numbers, reduced cytotoxic activi... Background: Natural killer (NK) cell phenotypes have reported to be implicated in the pathomechanism of Multiple Sclerosis (MS). Several investigators have observed reduced peripheral numbers, reduced cytotoxic activity, and altered CD56Dim and CD56Bright NK cell phenotypes. This current project, for the first time, investigates the NK cell cytotoxicity, calcium mobilisation and transient receptor potential melastatin 3 (TRPM3) surface expression. Methods: NK cell cytotoxic activity and calcium signaling were examined in CD56Dim and CD56Bright NK cells before and after stimulation using Ionomycin, Pregnenolone sulphate, 2-Aminoethoxydiphenyl borate and Thapsigargin. Purified NK cells were labelled with antibodies to determine TRPM3, CD69 and CD107a surface expression using flow cytometry. Results: Twenty-two MS patients and 22 healthy controls were recruited for this project. Twelve of the 22 previously received Alemtuzumab (Lemtrada&reg;) and the remaining ten reported nil medication. We report TRPM3 was significantly increased in untreated MS patients compared with healthy controls and treated MS patients (p-value 0.034). There was a significant decrease in CD69 surface expression on CD56Dim NK cell phenotype for untreated MS patients (p-value 0.031) and treated MS patients (p-value 0.036). We report altered calcium mobilisation in CD56Bright NK cells and to a lesser extent CD56Dim NK cells between healthy controls, treated and untreated MS patients. Conclusion: This investigation suggests variations in TRPM3 expression and calcium mobilisation of NK cells may be implicated in the pathogenesis of MS. Further investigation is required to determine the mechanism by which alemtuzumab alters calcium signaling in NK cells. 展开更多
关键词 Natural KILLER Cells Multiple SCLEROSIS CALCIUM SIGNALLING Transient RECEPTOR potential Melastatin 3 Ion CHANNELS
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基于形变势理论的掺杂计算Sb_(2)Se_(3)空穴迁移率
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作者 张冷 张鹏展 +4 位作者 刘飞 李方政 罗毅 侯纪伟 吴孔平 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第4期256-262,共7页
硒化锑(Sb_(2)Se_(3))是一种元素丰富、经济且无毒的太阳电池吸收层材料.太阳电池的性能在很大程度上取决于载流子的传输特性,然而在Sb_(2)Se_(3)中,这些特性尚未得到很好的理解.通过密度泛函理论和形变势理论,本文对纯Sb_(2)Se_(3)以... 硒化锑(Sb_(2)Se_(3))是一种元素丰富、经济且无毒的太阳电池吸收层材料.太阳电池的性能在很大程度上取决于载流子的传输特性,然而在Sb_(2)Se_(3)中,这些特性尚未得到很好的理解.通过密度泛函理论和形变势理论,本文对纯Sb_(2)Se_(3)以及掺杂了As,Bi的Sb_(2)Se_(3)的空穴传输特性进行研究,计算并分析了影响迁移率的3个关键参数:有效质量、形变势和弹性常数.结果显示,有效质量对迁移率具有最大影响,掺杂Bi的Sb_(2)Se_(3)表现出最高的平均迁移率.同时发现,Sb_(2)Se_(3)的空穴迁移率呈现出明显的各向异性,其中x方向的迁移率远高于y,z方向,这应该与x方向的原子主要以较强的共价键连接,而y,z方向以较弱的范德瓦耳斯力连接有关.载流子传输能力强的方向有助于有效传输和收集光生载流子,本研究从理论上强调了控制Sb_(2)Se_(3)沿特定方向生长的重要性. 展开更多
关键词 Sb_(2)Se_(3) 迁移率 形变势 掺杂
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A novel knowledge-based potential for RNA 3D structure evaluation
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作者 杨毅 辜琦 +2 位作者 张本龚 时亚洲 邵志刚 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第3期526-533,共8页
Ribonucleic acids (RNAs) play a vital role in biology, and knowledge of their three-dimensional (3D) structure is required to understand their biological functions. Recently structural prediction methods have been... Ribonucleic acids (RNAs) play a vital role in biology, and knowledge of their three-dimensional (3D) structure is required to understand their biological functions. Recently structural prediction methods have been developed to address this issue, but a series of RNA 3D structures are generally predicted by most existing methods. Therefore, the evaluation of the predicted structures is generally indispensable. Although several methods have been proposed to assess RNA 3D structures, the existing methods are not precise enough. In this work, a new all-atom knowledge-based potential is developed for more accurately evaluating RNA 3D structures. The potential not only includes local and nonlocal interactions but also fully considers the specificity of each RNA by introducing a retraining mechanism. Based on extensive test sets generated from independent methods, the proposed potential correctly distinguished the native state and ranked near-native conformations to effectively select the best. Furthermore, the proposed potential precisely captured RNA structural features such as base-stacking and base-pairing. Comparisons with existing potential methods show that the proposed potential is very reliable and accurate in RNA 3D structure evaluation. 展开更多
关键词 RNA 3D structure evaluation knowledge-based potential
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