Synthesis and characterization of polymeric linseed oil grafted methyl methacrylate or styrene

Syntheses of wholly natural polymeric linseed oil (PLO) containing peroxide groups have been reported. Peroxidation, epoxidation and/or perepoxidation reactions of linseed oil, either under air or under oxygen flow at room temperature, resulted in polymeric peroxides, PLO-air and PLO-ofl, containing 1.3 and 3.5 wt.% of peroxide, with molecular weights of 2100 and 3780 Da, respectively. PLO-air contained cross-linked film up to 46.1 wt.% after a reaction time of 60 d, associated with a waxy, soluble part (PLO-air-s) that was isolated with chloroform extraction. PLO-ofl was obtained as a waxy, viscous liquid without any cross-linked part at the end of 24 d under visible irradation and oxygen flow. Polymeric peroxides, PLO-air-s and PLO-ofl initiated the free radical polymerization of both methyl methacrylate (MMA) and styreine (S) to give PMMA-graft-PLO and PS-graft-PLO graft copolymers in high yields with M-w varying from 37 to 470 kDa. The polymers obtained were characterized by FT-IR. H-1 NMR, TGA, DSC and GPC techniques. Cross-linked polymers were also studied by means of swelling measurements. PMNA-graft-PLO graft copolymer film samples were also used in cell-culture studies. Fibroblast cells were well adhered and proliferated on the copolymer film surfaces, which is important in tissue engineering

Probe of anomalous neutrino couplings to W and Z in medium energy setup of a beta-beam facility

Capability of medium energy setup of a beta beam experiment to probe new physics contributions to neutrino-W and neutrino-Z couplings are investigated. We employ the effective lagrangian approach of Buchmuller and Wyler and obtain 95% confidence level limits on neutrino couplings to these gauge bosons without assuming the flavor universality of the coupling of neutrinos. We show that a beta beam facility can place 3 to 20 times more restrictive limits than present ones on the deviations from the electron neutrino couplings in the Standard Model.Comment: 22 pages, 10 figure

Composite particles in the Theory of Quantum Hall Effect

The formation of composite particles in the electron liquid under QHE conditions discussed by Jain in generalizing Laughlins many-particle state is considered by using a model for two-dimensional guiding center configurations. Describing the self-consistent field of electron repulsion by a negative parabolic potential on effective centers and an inter-center amount we show that with increasing magnetic field the ground state of so-called primary composite particles $\nu=\frac{1}{q}$, $q=1,3,5,...$, is given for higher negative quantum numbers of the total angular momentum. By clustering of primary composite particles due to absorption or emission of flux quanta we explain phenomenologically the quasi-particle structure behind the series of relevant filling factors $\nu=\frac{p}{q}$, $p=1,2,3,...$. Our considerations show that the complicate interplay of electron-magnetic field and electron-electron interactions in QHE systems may be understood in terms of adding flux quanta $\Phi_0$ to charges $e$ and binding of charges by flux quanta.Comment: RevTeX 3.0, LaTeX, 10 pages, one table at th en

Anomalous WWgamma couplings in gamma-proton collision at the LHC

We examine the potential of pp-> p gamma p -> p W q X reaction to probe anomalous WWgamma couplings at the LHC. We find 95% confidence level bounds on the anomalous coupling parameters with various values of the integrated luminosity. We show that the reaction pp -> p gamma p -> p W q X at the LHC highly improve the current limits.Comment: 12 pages,3 figure

Search for electromagnetic properties of the neutrinos at the LHC

Exclusive production of neutrinos via photon-photon fusion provides an excellent opportunity to probe electromagnetic properties of the neutrinos at the LHC. We explore the potential of processes pp-> p gamma gamma p -> p nu anti-nu p and pp -> p gamma gamma p -> p nu anti-nu Z p to probe neutrino-photon and neutrino-two photon couplings. We show that these reactions provide more than seven orders of magnitude improvement in neutrino-two photon couplings compared to LEP limits.Comment: 11 pages, 4 tables, New backgrounds have been adde

Controlling the spontaneous spiking regularity via channel blocking on Newman-Watts networks of Hodgkin-Huxley neurons

We investigate the regularity of spontaneous spiking activity on Newman-Watts small-world networks consisting of biophysically realistic Hodgkin-Huxley neurons with a tunable intensity of intrinsic noise and fraction of blocked voltage-gated sodium and potassium ion channels embedded in neuronal membranes. We show that there exists an optimal fraction of shortcut links between physically distant neurons, as well as an optimal intensity of intrinsic noise, which warrant an optimally ordered spontaneous spiking activity. This doubly coherence resonance-like phenomenon depends significantly, and can be controlled via the fraction of closed sodium and potassium ion channels, whereby the impacts can be understood via the analysis of the firing rate function as well as the deterministic system dynamics. Potential biological implications of our findings for information propagation across neural networks are also discussed.Comment: 6 two-column pages, 5 figures; accepted for publication in Europhysics Letter

Double Inverse Stochastic Resonance with Dynamic Synapses

We investigate the behavior of a model neuron that receives a biophysically-realistic noisy post-synaptic current based on uncorrelated spiking activity from a large number of afferents. We show that, with static synapses, such noise can give rise to inverse stochastic resonance (ISR) as a function of the presynaptic firing rate. We compare this to the case with dynamic synapses that feature short-term synaptic plasticity, and show that the interval of presynaptic firing rate over which ISR exists can be extended or diminished. We consider both short-term depression and facilitation. Interestingly, we find that a double inverse stochastic resonance (DISR), with two distinct wells centered at different presynaptic firing rates, can appear.Comment: 12 pages, 7 figure

Kaluza-Klein Reduction of a Quadratic Curvature Model

Palatini variational principle is implemented on a five dimensional quadratic curvature gravity model, rendering two sets of equations which can be interpreted as the field equations and the stress-energy tensor. Unification of gravity with electromagnetism and the scalar dilaton field is achieved through the Kaluza-Klein dimensional reduction mechanism. The reduced curvature invariant, field equations and the stress-energy tensor in four dimensional spacetime are obtained. The structure of the interactions among the constituent fields is exhibited in detail. It is shown that the Lorentz force naturally emerges from the reduced field equations and the equations of the standard Kaluza-Klein theory is demonstrated to be intrinsically contained in this model.Comment: 10 page

The non-Abelian Weyl-Yang-Kaluza-Klein gravity model

The Weyl-Yang gravitation gauge theory is investigated in the framework of a pure higher-dimensional non-Abelian Kaluza-Klein background. We construct the dimensionally reduced field equations and energy-momentum tensors as well as the four dimensional modified Weyl-Yang+Yang-Mills theory from an arbitrary curved $internal$ space which is a extension of our previous model. In particular, the coset space case is considered to obtain explicitly the interactions between the gravitational and the gauge fields. The results not only appear to be generalization of the well-established equations of non-Abelian theory but also contain intrinsically the generalized gravitational source term and the Lorentz force density.Comment: 10 page

Probe of unparticles at the LHC in exclusive two lepton and two photon production via photon-photon fusion

The exclusive production pp->pXp is known to be one of the most clean channels at the LHC. We investigate the potential of processes pp -> p l-l+ p and pp-> p gamma gamma p to probe scalar and tensor unparticles by considering three different forward detector acceptances; 0.0015<xi<0.15, 0.0015<xi<0.5 and 0.1<xi<0.5. We obtain 95% confidence level sensitivity limits on the unparticle couplings for various integrated luminosities.Comment: 27 pages, 17 figure