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A proteomic landscape of pharmacologic perturbations for functional relevance
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作者 Zhiwei Liu Shangwen Jiang +8 位作者 Bingbing Hao Shuyu Xie Yingluo Liu Yuqi Huang Heng Xu Cheng Luo Min Huang Minjia Tan Jun-Yu Xu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第1期128-139,共12页
Pharmacological perturbation studies based on protein-level signatures are fundamental for drug discovery. In the present study, we used a mass spectrometry (MS)-based proteomic platform to profile the whole proteome ... Pharmacological perturbation studies based on protein-level signatures are fundamental for drug discovery. In the present study, we used a mass spectrometry (MS)-based proteomic platform to profile the whole proteome of the breast cancer MCF7 cell line under stress induced by 78 bioactive compounds. The integrated analysis of perturbed signal abundance revealed the connectivity between phenotypic behaviors and molecular features in cancer cells. Our data showed functional relevance in exploring the novel pharmacological activity of phenolic xanthohumol, as well as the noncanonical targets of clinically approved tamoxifen, lovastatin, and their derivatives. Furthermore, the rational design of synergistic inhibition using a combination of histone methyltransferase and topoisomerase was identified based on their complementary drug fingerprints. This study provides rich resources for the proteomic landscape of drug responses for precision therapeutic medicine. 展开更多
关键词 PROTEOMICS Drug PERTURBATION Drug target Drug combination
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Deep Learning Models Based on Weakly Supervised Learning and Clustering Visualization for Disease Diagnosis
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作者 Jingyao Liu Qinghe Feng +4 位作者 Jiashi Zhao Yu Miao Wei He Weili Shi Zhengang Jiang 《Computers, Materials & Continua》 SCIE EI 2023年第9期2649-2665,共17页
The coronavirus disease 2019(COVID-19)has severely disrupted both human life and the health care system.Timely diagnosis and treatment have become increasingly important;however,the distribution and size of lesions va... The coronavirus disease 2019(COVID-19)has severely disrupted both human life and the health care system.Timely diagnosis and treatment have become increasingly important;however,the distribution and size of lesions vary widely among individuals,making it challenging to accurately diagnose the disease.This study proposed a deep-learning disease diagnosismodel based onweakly supervised learning and clustering visualization(W_CVNet)that fused classification with segmentation.First,the data were preprocessed.An optimizable weakly supervised segmentation preprocessing method(O-WSSPM)was used to remove redundant data and solve the category imbalance problem.Second,a deep-learning fusion method was used for feature extraction and classification recognition.A dual asymmetric complementary bilinear feature extraction method(D-CBM)was used to fully extract complementary features,which solved the problem of insufficient feature extraction by a single deep learning network.Third,an unsupervised learning method based on Fuzzy C-Means(FCM)clustering was used to segment and visualize COVID-19 lesions enabling physicians to accurately assess lesion distribution and disease severity.In this study,5-fold cross-validation methods were used,and the results showed that the network had an average classification accuracy of 85.8%,outperforming six recent advanced classification models.W_CVNet can effectively help physicians with automated aid in diagnosis to determine if the disease is present and,in the case of COVID-19 patients,to further predict the area of the lesion. 展开更多
关键词 CLASSIFICATION COVID-19 deep learning SEGMENTATION unsupervised learning weakly supervised
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Long-range adsorbate interactions mediated by two-dimensional Dirac fermions
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作者 王晓慧 付振国 +2 位作者 王志刚 迟锋 张平 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期596-603,共8页
We provide here an analytical formalism to describe the indirect interaction between adsorbed atom or molecule pairs mediated by two-dimensional(2D)Dirac fermions.We show that in contrast to the case of traditional 2D... We provide here an analytical formalism to describe the indirect interaction between adsorbed atom or molecule pairs mediated by two-dimensional(2D)Dirac fermions.We show that in contrast to the case of traditional 2D electron gas,in the 2D Dirac system,the long-range interaction behaves as 1/r^(3) decaying Friedel oscillation.This analytical formalism is fully consistent with a tight-binding numerical calculation of honeycomb lattices.Our formalism is suitable for the realistic 2D Dirac materials,such as graphene and surface states of three-dimensional topological insulators. 展开更多
关键词 GRAPHENE Green's function Dirac fermions
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A (2+1)-Dimensional Displacement Shallow Water Wave System 被引量:6
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作者 刘萍 楼森岳 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第9期3311-3314,共4页
A new (2+1)-dimensional shallow water wave system, the (2+1)-dimensional displacement shallow water wave system (2DDSWWS), is constructed by applying variational principle of the analytic mechanics under the L... A new (2+1)-dimensional shallow water wave system, the (2+1)-dimensional displacement shallow water wave system (2DDSWWS), is constructed by applying variational principle of the analytic mechanics under the Lagrange coordinates. The general travelling wave solution is expressed as an elliptic integral. A special case is explicitly expressed by the Jacobi elliptic function which is a generalization of the solitary wave solution. Compared with some traditional (2+1)-dimensional shallow water wave systems such as the Kadomtsev Petviashvili (KP) description under the Euler coordinates, the 2DDSWWS has some its own advantages. In addition, the KP equation can also be derived from the 2DDSWWS under the weak two-dimensional long-wave approximation. 展开更多
关键词 the power-law exponents precipitation durative abrupt precipitation change
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Modified (2+1)-dimensional displacement shallow water wave system and its approximate similarity solutions 被引量:4
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作者 刘萍 付培凯 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期30-36,共7页
Recently, a new (2+1)-dimensional shallow water wave system, the (2+1)-dlmenslonal displacement shallow water wave system (2DDSWWS), was constructed by applying the variational principle of the analytic mechan... Recently, a new (2+1)-dimensional shallow water wave system, the (2+1)-dlmenslonal displacement shallow water wave system (2DDSWWS), was constructed by applying the variational principle of the analytic mechanics in the Lagrange coordinates. The disadvantage is that fluid viscidity is not considered in the 2DDSWWS, which is the same as the famous Kadomtsev-Petviashvili equation and Korteweg-de Vries equation. Applying dimensional analysis, we modify the 2DDSWWS and add the term related to the fluid viscidity to the 2DDSWWS. The approximate similarity solutions of the modified 2DDSWWS (M2DDSWWS) is studied and four similarity solutions are obtained. For the perfect fluids, the coefficient of kinematic viscosity is zero, then the M2DDSWWS will degenerate to the 2DDSWWS. 展开更多
关键词 modified (2+1)-dimensional displacement shallow water wave system viscidity approx-imate similarity solutions Kadomtsev-Petviashvili equation
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Symmetry Analysis of Nonlinear Incompressible Non-Hydrostatic Boussinesq Equations 被引量:2
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作者 刘萍 高晓楠 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期609-614,共6页
对称(2+1 ) 维的非线性的不可压缩的非静水力学的 Boussinesq (INHB ) 方程,描述大气的严肃波浪(GW ) ,在这篇论文被研究。谎言对称和相应减小借助于古典谎言组途径被获得。计算证明 INHB 方程在一些 Galilee 的转变下面是不变的,放... 对称(2+1 ) 维的非线性的不可压缩的非静水力学的 Boussinesq (INHB ) 方程,描述大气的严肃波浪(GW ) ,在这篇论文被研究。谎言对称和相应减小借助于古典谎言组途径被获得。计算证明 INHB 方程在一些 Galilee 的转变下面是不变的,放大转变,和时空翻译。对称减小方程和 INHB 方程的类似的答案被建议。 展开更多
关键词 Boussinesq方程 LIE对称性 非线性分析 不可压缩 静压 大气重力波 伽利略变换 李群方法
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Study on the Physiological,Cellular,and Morphological Aspects of the Postharvest Development of Cut Lily Flowers 被引量:2
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作者 Yushan Zhang Dexin Zhong +1 位作者 Zhanfei Liu Jiawei Gao 《Horticultural Plant Journal》 SCIE CSCD 2021年第2期149-158,共10页
It is of great practical significance to study the development process of cut lily for regulating flowering and preservation.In this study,the developmental process of lily cut flower was explored from cellular,morpho... It is of great practical significance to study the development process of cut lily for regulating flowering and preservation.In this study,the developmental process of lily cut flower was explored from cellular,morphological,and physiological aspects.Froma morphological aspect,the tepal edge grows faster than the midrib.The midrib groove of the flowering stage is wider than that of bud stage.The fast-growing edge of the petals results in the midrib bending outward.Moreover,the rapid growth of the stamens and stigmas also contributes to bud cracking.From the cellular aspect,in the bud stage there were more wrinkles in the outer epidermal cell wall of the tepal than those in the inner epidermal cell wall,indicating that asymmetric structural differences exist from the beginning of lily development.From a physiological aspect,from the bud cracking stage to the senescence stage,a variety of substances in the tepal cells gradually decreased,including total nitrogen,total phosphorus,total potassium,total calcium,starch,soluble sugar,and soluble protein,but not malondialdehyde.These results indicate that the asymmetric growth caused by this structural difference is responsible for flowering.The wrinkles in the cell wall can be regarded as indicators of senescent cells and are caused by the degradation of the cell wall and the loss of intracellular turgor pressure.The differences in the epidermal cells between the inner and outer tepal indicated ultrastructural changes in the tepal cells.The bud and flowering stages are maintained by the tepals acting as a sink.After flowering,the tepals gradually change from a sink to a source organ.Senescence of the cut lily flowers was caused by the decomposition of intracellular compounds in the tepals and the remobilization of nutrients from the tepals to the developing organs. 展开更多
关键词 cut lily epidermal cell MIDRIB tepal WRINKLE
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Coupled Nonlinear Schrodinger Equation: Symmetries and Exact Solutions 被引量:2
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作者 LIU Ping LOU Sen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第1期27-34,共8页
非线性的 Schr&#246;dinger (CNLS ) 方程为大气的严肃波浪从管理系统导出的 a coupled 的对称,对称减小,和准确解决方案在这篇论文借助于古典谎言组途径被研究。计算证明 CNLS 方程在一些 Galilee 的转变下面是不变的,放大转变... 非线性的 Schr&#246;dinger (CNLS ) 方程为大气的严肃波浪从管理系统导出的 a coupled 的对称,对称减小,和准确解决方案在这篇论文借助于古典谎言组途径被研究。计算证明 CNLS 方程在一些 Galilee 的转变下面是不变的,放大转变,阶段移动,和时空翻译。一些平常的微分方程从 CNLS 方程被导出。包括为 CNLS 方程的信封 cnoidal 波浪,独居的波浪和三角法的功能答案的几个准确答案被使用对称也获得。 展开更多
关键词 耦合非线性薛定谔方程 对称性 精确解 NLS方程 大气重力波 伽利略变换 常微分方程 三角函数解
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Modified constraint-induced movement therapy alters synaptic plasticity of rat contralateral hippocampus following middle cerebral artery occlusion 被引量:19
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作者 Bei-Yao Gao Dong-Sheng Xu +6 位作者 Pei-Le Liu Ce Li Liang Du Yan Hua Jian Hu Jia-Yun Hou Yu-Long Bai 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第6期1045-1057,共13页
Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.Ho... Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.However,the molecular mechanism underlying its efficacy remains unclear.In this study,a middle cerebral artery occlusion(MCAO)rat model was produced by the suture method.Rats received modified constraint-induced movement therapy 1 hour a day for 14 consecutive days,starting from the 7^th day after middle cerebral artery occlusion.Day 1 of treatment lasted for 10 minutes at 2r/min,day 2 for 20 minutes at 2 r/min,and from day 3 onward for 20 minutes at 4 r/min.CatWalk gait analysis,adhesive removal test,and Y-maze test were used to investigate motor function,sensory function as well as cognitive function in rodent animals from the 1st day before MCAO to the 21^st day after MCAO.On the 21^st day after MCAO,the neurotransmitter receptor-related genes from both contralateral and ipsilateral hippocampi were tested by micro-array and then verified by western blot assay.The glutamate related receptor was shown by transmission electron microscopy and the glutamate content was determined by high-performance liquid chromatography.The results of behavior tests showed that modified constraint-induced movement therapy promoted motor and sensory functional recovery in the middle cerebral artery-occluded rats,but had no effect on cognitive function.The modified constraint-induced movement therapy upregulated the expression of glutamate ionotropic receptor AMPA type subunit 3(Gria3)in the hippocampus and downregulated the expression of the beta3-adrenergic receptor gene Adrb3 and arginine vasopressin receptor 1 A,Avprla in the middle cerebral artery-occluded rats.In the ipsilateral hippocampus,only Adra2 a was downregulated,and there was no significant change in Gria3.Transmission electron microscopy revealed a denser distribution the more distribution of postsynaptic glutamate receptor 2/3,which is an a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor,within 240 nm of the postsynaptic density in the contralateral cornu ammonis 3 region.The size and distribution of the synaptic vesicles within 100 nm of the presynaptic active zone were unchanged.Western blot analysis showed that modified constraint-induced movement therapy also increased the expression of glutamate receptor 2/3 and brain-derived neurotrophic factor in the hippocampus of rats with middle cerebral artery occlusion,but had no effect on Synapsin I levels.Besides,we also found modified constraint-induced movement therapy effectively reduced glutamate content in the contralateral hippocampus.This study demonstrated that modified constraint-induced movement therapy is an effective rehabilitation therapy in middle cerebral artery-occluded rats,and suggests that these positive effects occur via the upregulation of the postsynaptic membrane a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor expression.This study was approved by the Institutional Animal Care and Use Committee of Fudan University,China(approval No.201802173 S)on March 3,2018. 展开更多
关键词 BRAIN-DERIVED neurotrophic factor glutamate HIPPOCAMPUS m CIMT middle cerebral artery occlusion MODIFIED constraint-induced movement therapy α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor
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Exact solutions and residual symmetries of the Ablowitz–Kaup–Newell–Segur system 被引量:2
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作者 刘萍 曾葆青 +1 位作者 杨建荣 任博 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期125-131,共7页
The residual symmetries of the Ablowitz-Kaup-Newell-Segur (AKNS) equations are obtained by the truncated Painleve analysis. The residual symmetries for the AKNS equations are proved to be nonlocal and the nonlocal r... The residual symmetries of the Ablowitz-Kaup-Newell-Segur (AKNS) equations are obtained by the truncated Painleve analysis. The residual symmetries for the AKNS equations are proved to be nonlocal and the nonlocal residual symmetries are extended to the local Lie point symmetries of a prolonged AKNS system. The local Lie point symme- tries of the prolonged AKNS equations are composed of the residual symmetries and the standard Lie point symmetries, which suggests that the residual symmetry method is a useful complement to the classical Lie group theory. The calcula- tion on the symmetries shows that the enlarged equations are invariant under the scaling transformations, the space-time translations, and the shift translations. Three types of similarity solutions and the reduction equations are demonstrated. Furthermore, several types of exact solutions for the AKNS equations are obtained with the help of the symmetry method and the Backlund transformations between the AKNS equations and the Schwarzian AKNS equation. 展开更多
关键词 residual symmetries Ablowitz-Kaup-Newell-Segur equation exact solution Backlund transformation
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REDUCING THE PEAK-TO-AVERAGE POWER RATIO OF OFDM SYSTEM WITH LOW COMPLEXITY 被引量:2
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作者 Luo Renze Jing Longjiang +2 位作者 Luo Lang Li Jie Zhu Weile 《Journal of Electronics(China)》 2006年第1期26-28,共3页
This paper proposes a companding scheme, where small signals are enlarged and large signals are reduced, to reduce the Peak-to-Average Power Ratio(PAPR). Computer simulation results show that the proposed technique ha... This paper proposes a companding scheme, where small signals are enlarged and large signals are reduced, to reduce the Peak-to-Average Power Ratio(PAPR). Computer simulation results show that the proposed technique has two advantages at least when compared with the conventional methods such as partial transmit sequence, selective mapping and the previous companding. First, it gets better PAPR performances with a lower complexity. Second, the scheme achieves greater performances gain with hardly any damnification of OFDM signals in some degree. 展开更多
关键词 正交频分复用 OFDM 功率比率 PAPR 压缩扩展器
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Prediction of the Logistics Demand Based on an Innovative Mixed Model: an Empirical Case from Nanping City,China 被引量:2
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作者 王波 魏乐琴 +3 位作者 陈金雄 蔡尚斌 张立中 边舫 《Journal of Donghua University(English Edition)》 EI CAS 2019年第5期498-506,共9页
The research intends to make scientific prediction of the logistics demand of Nanping City based on mathematical model calculation so as to provide reasonable strategic guidance for the sustainable and healthy develop... The research intends to make scientific prediction of the logistics demand of Nanping City based on mathematical model calculation so as to provide reasonable strategic guidance for the sustainable and healthy development of urban logistics industry.It constructs a comprehensive index system composed of freight volume and other eight relevant economic indices to form the foundation for the model construction.Combining forecasting models of principal component regression and GM(1,1)together,it makes mathematical calculation to predict the logistics demand of Nanping City from the years 2018 to 2022.The research makes systematical analyses of the indices influencing the precise prediction of logistics demand from a new perspective,which offers an innovative and practical option for urban logistics prediction.In line with the prediction,it offers some suggestions for the improvement of demand prediction and some strategies for the better development of the logistics industry in Nanping City. 展开更多
关键词 regional LOGISTICS DEMAND PREDICTION principal component regression GM(1 1)prediction
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A class of coupled nonlinear Schrdinger equations:Painlev'e property,exact solutions,and application to atmospheric gravity waves 被引量:1
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作者 刘萍 李子良 楼森岳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第11期1383-1404,共22页
The Painleve integrability and exact solutions to a coupled nonlinear Schrodinger (CNLS) equation applied in atmospheric dynamics are discussed. Some parametric restrictions of the CNLS equation are given to pass th... The Painleve integrability and exact solutions to a coupled nonlinear Schrodinger (CNLS) equation applied in atmospheric dynamics are discussed. Some parametric restrictions of the CNLS equation are given to pass the Painleve test. Twenty periodic cnoidal wave solutions are obtained by applying the rational expansions of fundamental Jacobi elliptic functions. The exact solutions to the CNLS equation are used to explain the generation and propagation of atmospheric gravity waves. 展开更多
关键词 coupled nonlinear SchrSdinger equation Painleve property exact solution atmospheric gravity wave
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Effect of Different Oligosaccharides on Immunity and Production Performance of Piglets 被引量:1
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作者 LI Mei LIU Wen-li +5 位作者 ZHAO Gui-ying YU Li-ming WU Yong-hao WU Yan-fen PAN Zi-qiang SHEN Zhi-hua 《Animal Husbandry and Feed Science》 CAS 2010年第8期9-11,共3页
[ Objective] To study the effects of different oligosaccharides on immunity and production performance of piglets.[ Method] A total of 75 Yorkshire x Rongchang piglets were assigned into five groups, 15 in each group.... [ Objective] To study the effects of different oligosaccharides on immunity and production performance of piglets.[ Method] A total of 75 Yorkshire x Rongchang piglets were assigned into five groups, 15 in each group. Isomalto-oligosaccharide ( IMO), fructo-oligosaccharide ( FOS), mannan-oligosacchadde (MOS), and mixed oligosacchadde were supplemented to basal diet (7.5 g/kg), respectively. The control group was also set. The experimental period lasted for 53 d. The clinic symptoms and diarrhea were observed. All piglets were weighed once a week. Feed intake was also recorded. Blood was collected via precaval vein for determination of immunology indexes at the age of 30 and 60 d, respectively. [ Result] The IMO and FOS enhanced cellular immunity of 30-day-old piglets significantly (P 〈 0.05), and the IMO also enhanced their humoral immunity. The MOS enhanced cellular immunity and humoral immunity of 60-day-old piglets significantly (P 〈 0.05). It also improved production performance largest, and its diarrhea rate was the lowest. [ Conclusion] Different oligosaccharides have various effects on immunity and production performance of oiolets. 展开更多
关键词 OLIGOSACCHARIDES PIGLETS Cellular immunity Humoral immunity
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A Coupled Hybrid Lattice: Its Related Continuous Equation and Symmetries
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作者 刘萍 付培凯 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期5-10,共6页
The hybrid lattice, known as a discrete Korteweg-de Vries (KdV) equation, is found to be a discrete modified Korteweg-de Vries (mKdV) equation in this paper. The coupled hybrid lattice, which is pointed to be a discre... The hybrid lattice, known as a discrete Korteweg-de Vries (KdV) equation, is found to be a discrete modified Korteweg-de Vries (mKdV) equation in this paper. The coupled hybrid lattice, which is pointed to be a discrete coupled KdV system, is also found to be discrete form of a coupled mKdV systems. Delayed differential reduction system and pure difference systems are derived from the coupled hybrid system by means of the symmetry reduction approach. Cnoidal wave, positon and negaton solutions for the coupled hybrid system are proposed. 展开更多
关键词 混合动力系统 连续方程 自耦合 对称性 KDV系统 离散形式 德弗里斯 椭圆余弦波
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Photon-Assisted Heat Generation by Electric Current in a Quantum Dot Attached to Ferromagnetic Leads
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作者 迟锋 孙连亮 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第11期87-91,共5页
Heat generated by electric current in a quantum dot device contacting a phonon bath is studied using the non- equilibrium Green function technique. Spin-polarized current is generated owing to the Zeeman splitting of ... Heat generated by electric current in a quantum dot device contacting a phonon bath is studied using the non- equilibrium Green function technique. Spin-polarized current is generated owing to the Zeeman splitting of the dot level. The current's strength and the spin polarization are further manipulated by changing the frequency of an applied photon field and the ferromagnetism on the leads. We find that the associated heat by this spin- polarized current emerges even if the bias voltage is smaller than the phonon energy quanta and obvious negative differential of the heat generation develops when the photon frequency exceeds that of the phonon. It is also found that both the strength and the resonant peaks' position of the heat generation can be tuned by changing the value and the arrangement configurations of the magnetic moments of the two leads, and then provides an effective method to generate large spin-polarized current with weak heat. Such a result may be useful in designing low energy consumption spintronic devices. 展开更多
关键词 by on heat is of in Photon-Assisted Heat Generation by Electric Current in a Quantum Dot Attached to Ferromagnetic Leads
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Dispersing and Doping of BaTiO_3 Powder by Adsorption
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作者 苏滔珑 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第5期644-646,共3页
Dispersing and doping of BaTiO3 powder by adsorption method were investigated. Ultrafine BaTiO3 powders were dispersed in the aqueous with ammoniumized citrate (NHa-CA) or ammoniumized citric lanthanum chelate (NH4... Dispersing and doping of BaTiO3 powder by adsorption method were investigated. Ultrafine BaTiO3 powders were dispersed in the aqueous with ammoniumized citrate (NHa-CA) or ammoniumized citric lanthanum chelate (NH4-La-CA) as dispersant by ultrasonic bath. Better dispersion of BaTiO3 slurry was obtained in the aqueous with NH4-La-CA than that of NH4-CA when the mass ratio of citric acid (CA) to BaTiO3 was less than 0,007. The pH value hardly affects the dispersion property of BaTiO3 suspension dispersed by NH4-La-CA. BaTiO3 powder could be well dispersed (median size D50=0.45 μm) and also doped with high uniformity of added components by adsorbing citric acid chelate on surface. Compared with solid mixing, better microstructure and properties of La/Mn codoped ceramics were obtained by adsorption method. 展开更多
关键词 BATIO3 ADSORPTION dispersion DOPING
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Enhanced spin-dependent thermopower in a double-quantum-dot sandwiched between two-dimensional electron gases
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作者 迟锋 付振国 +1 位作者 刘黎明 张平 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期523-530,共8页
We study the spin-dependent thermopower in a double-quantum-dot(DQD) embedded between the left and right two-dimensional electron gases(2DEGs) in doped quantum wells under an in-plane magnetic field. When the separati... We study the spin-dependent thermopower in a double-quantum-dot(DQD) embedded between the left and right two-dimensional electron gases(2DEGs) in doped quantum wells under an in-plane magnetic field. When the separation between the DQD is smaller than the Fermi wavelength in the 2DEGs, the asymmetry in the dots' energy levels leads to pronounced quantum interference effects characterized by the Dicke line-shape of the conductance, which are sensitive to the properties of the 2DEGs. The magnitude of the thermopower, which denotes the generated voltage in response to an infinitesimal temperature difference between the two 2DEGs under vanishing charge current, will be obviously enhanced by the Dicke effect. The application of the in-plane magnetic field results in the polarization of the spin-up and spin-down conductances and thermopowers, and enables an efficient spin-filter device in addition to a tunable pure spin thermopower in the absence of its charge counterpart. 展开更多
关键词 quantum DOT spin-dependent THERMOPOWER TWO-DIMENSIONAL ELECTRON GASES
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Photon-mediated spin-polarized current in a quantum dot under thermal bias
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作者 迟锋 刘黎明 孙连亮 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第3期489-494,共6页
Spin-polarized current generated by thermal bias across a system composed of a quantum dot (QD) connected to metallic leads is studied in the presence of magnetic and photon fields. The current of a certain spin ori... Spin-polarized current generated by thermal bias across a system composed of a quantum dot (QD) connected to metallic leads is studied in the presence of magnetic and photon fields. The current of a certain spin orientation vanishes when the dot level is aligned to the lead's chemical potential, resulting in a 100% spin-polarized current. The spin-resolved current also changes its sign at the two sides of the zero points. By tuning the system's parameters, spin-up and spin-down currents with equal strength may flow in opposite directions, which induces a pure spin current without the accompany of charge current. With the help of the thermal bias, both the strength and the direction of the spin-polarized current can be manipulated by tuning either the frequency or the intensity of the photon field, which is beyond the reach of the usual electric bias voltage. 展开更多
关键词 quantum dot spin-polarized current thermal bias photon field
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Effects of short gamete co-incubation in human in vitro fertilization
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作者 曾勇 宋成 张微 《生殖医学杂志》 CAS 2011年第B12期71-74,共4页
Traditionally oocytes have been exposed to sperm overnight for 16-20 h.This long period of co-incubation, however,has been shown to create problems with high levels of reactive oxygen species(ROS),which may affect emb... Traditionally oocytes have been exposed to sperm overnight for 16-20 h.This long period of co-incubation, however,has been shown to create problems with high levels of reactive oxygen species(ROS),which may affect embryo viability and cause hardening of the zona pellucida.Recently,several positive and negative effects of reducing the co-incubation time to 90-120 min were reported.The objective of this review was to discuss whether short exposure of oocytes to sperm in vitro might affect the clinical results and several problems arose in short gamete co-incubation. 展开更多
关键词 体外受精 配子 孵化 人类 卵母细胞 培养周期 培养时间 临床效果
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