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Uniform convergence of the p-Bieberbach polynomials in domains with zero angles

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Science China Mathematics 2015年第5期58卷 1063-1078页

作者： ABDULLAYEV Fahreddin g ZKARTEPE Pelin n Department of Mathematics Faculty of Arts and Science Mersin University

Let g C C be a simply connected domain whose boundary L ：= g is a Jordan curve and 0 ∈ g. Let w = φ（z） be the conformal mapping of g onto the disk B（0, r0）：= {w ：｜w｜〈 r0）, satisfying φ0（0） = 0, φ＇t（0） = 1. We consider the following extremal problem for p 〉 0：∫∫g｜φ＇（z）-P＇n（z）｜Pdσz→min in the class of all polynomials Pn（z） of degree not exceeding n with Pn（0） = 0, P＇n （0）=- 1. The solution to this extremal problem is called the p-Bieberbach polynomial of degree n for the pair （g, 0）. We study the uniform convergence of the p-Bieberbach polynomials Bn,p（z） to the φ（z） on g^- with interior and exterior zero angles determined depending on the properties of boundary arcs and the degree of their ＂touch＂.

关键词： conformal mapping quasiconformal curve Bieberbach polynomials complex approximation

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-Segura Aleksandra Polishchuk Laura nadal Marta Tomàs Carolina Silvera-Simón Manel M.Santafé Maria A.Lanuza Unitat d’Histologia i neurobiologia(UHneurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75nTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the n-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

Quantum dynamics of charge transfer on the one-dimensional lattice:Wave packet spreading and recurrence

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Chinese Physics B 2016年第1期25卷 817-830页

作者： V n Likhachev O I Shevaleevskii g A Vinogradov Emanuel Institute of Biochemical Physics Russian Academy of Sciences

The wave function temporal evolution on the one-dimensional （ID） lattice is considered in the tight-binding approxi- mation. The lattice consists of n equal sites and one impurity site （donor）. The donor differs from other lattice sites by the on-site electron energy E and the intersite coupling C. The moving wave packet is formed from the wave function initially localized on the donor. The exact solution for the wave packet velocity and the shape is derived at different values E and C. The velocity has the maximal possible group velocity v = 2. The wave packet width grows with time -t1/3 and its amplitude decreases ,- t-1/3. The wave packet reflects multiply from the lattice ends. Analytical expressions for the wave packet front propagation and recurrence are in good agreement with numeric simulations.

关键词： quantum dynamics tight-binding approximation charge transport

Electro–optic response in thin smectic C* film with chevron structures

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Chinese Physics B 2016年第12期25卷 337-343页

作者： Aleksey A Kudreyko nail g Migranov Dana n Migranova Ufa State Petroleum Technological University Department of Physics Bashkir State Pedagogical University Department of General and Theoretical Physics

The effects in electrostatic models of chevron surface-stabilized ferroelectric liquid crystals are investigated through numerical modeling. To study smectic C＊ director distribution within the cell, we consider two nonlinear approaches： the chevron interface does not interplay with the electric field; the electric field interplays with the chevron interface. The obtained results of the director field distribution are compared with the earlier linearized studies. We find that whether or not the electric field interplays with the chevron interface, the electro-optic response requires a generalized approach for its description. The threshold electric field, which is necessary for switching between two stable director states in the chevron cell is evaluated. This study suggests that, in many cases of practical interest, electro-optic response to the electric field and the threshold electric field can be precisely estimated. We argue that, beside being numerically efficient, our approach provides a convenient and a novel standpoint for looking at the electro-optic response problem.

关键词： surface-stabilized ferroelectric liquid crystal chevron structure thin films bistability Euler'sequation

Destruction of an advanced malignant tumour by direct electrical current-case report

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Health 2010年第9期2卷 1049-1053页

作者： chima Oji John Ani 不详

We carried out a study on the effect of low-level direct current on cancer by using it to treat a woman who had a large malignant squamous cell carcinoma of the sinus cavity. We used a device that produced low-level direct current and passed the current through the tumour via a 4 × 4 cm flat aluminium foil and a needle electrode that was insulated along its entire length except for the portion actually inserted into the tumour. The treatment was eight hourly daily and lasted for eight weeks. The therapy resulted in the total remission of the tumour and a feeling of wellness by the patient. This finding implies promising therapeutic potential for the use of direct electrical current as a simple, effective, low cost alternative for the treatment of cancer.

关键词： Destruction Malignant Tumour Human Patient Direct Electrical Current

Magnetically propelled Carreau fluid flow over penetrable sensor surface influenced by thermal radiation,Joule heating and heat generation

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Communications in Theoretical Physics 2022年第2期74卷 9-18页

作者： B J gireesha B nagaraja n Srikantha n g Rudraswamy A Felicita Department of Studies and Research in Mathematics Kuvempu UniversityShankaraghattaShivamoggaKarnatakaIndia Department of Mathematics MS Ramaiah Institute of TechnologyBangaloreIndia Department of Mathematics P.C.Jabin Science College(Autonomous)HubballiIndia

This examination emphasizes the analysis of thermal transmission of Carreau fluid flow on a permeable sensor surface equipped with radiation,Joule heating,an internal heat source,and a magnetic *** the above effects and assumptions,the equations that administer the flow are formulated.A configured system of equations is productively reduced to a system of ordinary differential *** reduced system is then dealt with using the Runge–Kutta-Fehlberg fourth–fifth order tool equipped by the shooting *** numerical solutions are utilized to plot graphs and *** conclusion of the study outlines some important findings such as the power law index,the thermal radiation parameter and the heat source parameter enhance the thermal panel whereas the Weissenberg number deescalates the *** power law index and permeable velocity decrease the velocity panel *** representation of streamlines of the flow has been given to strengthen the study.A detailed description has been produced about the results obtained in the study.

关键词： sensor surface Carreau fluid squeezed flow thermal radiation heat generation

尼日利亚Ariki油田地层层序、构造格架与油气运聚

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石油勘探与开发 2016年第1期43卷 77-83页

作者： AHAnEKU C V OKORO A U ODOH B I AnOMnEZE D O chima K I EJEKE C F OKOLI I n Department of geological Sciences Nnamdi Azikiwe University Department of Subsurface and Engineering Nubian Group Department of Physics/geology/geophysics Federal University

综合应用测井和三维地震数据,对尼日尔三角洲盆地西部浅海沉积带Ariki油田的构造格架和地层层序进行了解释,并开展了断裂控藏分析。该油田主力储集层Agbada组内识别出5个最大洪泛面和5个层序界面,构造格架受控于伸展构造活动所形成的主... 详细信息

综合应用测井和三维地震数据,对尼日尔三角洲盆地西部浅海沉积带Ariki油田的构造格架和地层层序进行了解释,并开展了断裂控藏分析。该油田主力储集层Agbada组内识别出5个最大洪泛面和5个层序界面,构造格架受控于伸展构造活动所形成的主断层、次级断层以及滚动背斜。研究区共发育7条断层,可划分为3个主断层和4个次级断层;在油田西翼,次级断层活动形成类似地堑和地垒的构造。通过断距分析,认为在1 800 ms以下,主断层断距加大,主断层作为油气运移通道;在1 800 ms以上,主断层断距变小,可以作为油气圈闭遮挡。研究区存在四面下倾的滚动背斜和次级断层控制的三面下倾闭合圈闭等多种远景构造圈闭,有利于提升石油区带的规模勘探潜力。

关键词：尼日尔三角洲 Ariki油田地层层序构造格架油气运聚滚动背斜断层封堵性

Calculation of the gluon Distribution Function Using Alternative Method for the Proton Structure Function

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Communications in Theoretical Physics 2003年第5X期40卷 551-557页

作者： n.ghahramany g.R.Boroun PhysicsDepartment ShirazUniversityShiraz71454Iran

A calculation of the proton structure function F2(x,Q^2) is reported with an approximation method that relates the reduced cross section derivative and the F2(x, Q^2) scaling violation at low x by using quadratic form for the structure function. This quadratic form approximation method can be used to determine the structure function F2 (x, Q^2) from the HERA reduced cross section data taken at low x. This new approach can determine the structure functions F2(x,Q^2) with reasonable precision even for low x values which have not been investigated. We observe that the Q^2 dependence is quadratic over the full kinematic covered range. To test the validity of our new determined structure functions, we find the gluon distribution function in the leading order approximation with our new calculation for the structure functions and compare them with the QCD parton distribution functions.

关键词：质子结构函数胶子量子色动力学无弹性散射 QCD 强相互作用

DIFFUSIVE-DISPERSIVE TRAVELIng WAVES AnD KInETIC RELATIOnS IV. COMPRESSIBLE EULER EQUATIOnS

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Chinese Annals of Mathematics,Series B 2003年第1期24卷 17-34页

作者： n. BEDJAOUI P.g.LEFLOCH Centre de Mathematiques Appliquees & Centre national de la Recherche Scientifique UMR 7641 Ecole Polytechnique 91128 Palaiseau Cedex France. INSSET Universite de Picardie 48 rue Raspail 02109 Saint-Quentin France.Centre de Mathematiques Appliquees & Centre National de la Recherche Scientifique UMR 7641 Ecole Polytechnique 91128 Palaiseau Cedex France.

The authors consider the Euler equations for a compressible fluid in one space dimensionwhen the equation of state of the fluid does not fulfill standard convexity assumptions andviscosity and capillarity effects are taken into account. A typical example of nonconvex con-stitutive equation for fluids is Van der Waals' equation. The first order terms of these partialdifferential equations form a nonlinear system of mixed (hyperbolic-elliptic) type. For a class ofnonconvex equations of state, an existence theorem of traveling waves solutions with arbitrarylarge amplitude is established here. The authors distinguish between classical (compressive) andnonclassical (undercompressive) traveling waves. The latter do not fulfill Lax shock inequali-ties, and are characterized by the so-called kinetic relation, whose properties are investigatedin this paper.

关键词： Elasto dynamics Phase transitions Hyperbolic conservation law Diffusion Dispersion Shock wave Undercompressive Entropy inequality Kinetic relation