Supersymmetric economical 3-3-1 model

The supersymmetric extension of the economical 3-3-1 model is presented. The constraint equations and the gauge boson identification establish a relation between the vacuum expectation values (VEVs) at the top and bottom elements of the Higgs triplet $\chi$ and its supersymmetric counterpart $\chi^\prime$. Because of this relation, the exact diagonalization of neutral gauge boson sector has been performed. The gauge bosons and their associated Goldstone ones mix in the same way as in non-supersymmetric version. This is also correct in the case of gauginos. The eigenvalues and eigenstates in the Higgs sector are derived. The model contains a heavy neutral Higgs boson with mass equal to those of the neutral non-Hermitian gauge boson $X^0$ and a charged scalar with mass equal to those of the $W$ boson in the standard model, i. e. $m_{\varrho_1} = m_W$. This result is in good agreement with the present estimation: $m_{H^\pm} > 79.3$ GeV, CL= 95 %. We also show that the boson sector and the fermion sector gain masses in the same way as in the non-supersymmetric case.Comment: 33 page

3D Printing of a Polymer Bioactive Glass Composite for Bone Repair

A major limitation of synthetic bone repair is insufficient vascularization of the interior region of the scaffold. In this study, we investigated the 3D printing of adipose derived mesenchymal stem cells (AD-MSCs) with polycaprolactone (PCL)/bioactive glass composite in a single process. This offered a three-dimensional environment for complex and dynamic interactions that govern the cell’s behavior in vivo. Borate based bioactive (13-93B3) glass of different concentrations (10 to 50 weight %) was added to a mixture of PCL and organic solvent to make an extrudable paste. AD-MSCs suspended in Matrigel was extruded as droplets using a second syringe. Scaffolds measuring 10x10x1 mm3 in overall dimensions with a filament width of ~500 μm and pore sizes ranging from 100 to 200 μm were fabricated. Strut formability dependence on paste viscosity, scaffold integrity, and printing parameters for droplets of ADMSCs suspended in Matrigel were investigated

Bounds on Higgs and Gauge--Boson Interactions from LEP2 Data

We derive bounds on Higgs and gauge--boson anomalous interactions using the LEP2 data on the production of three photons and photon pairs in association with hadrons. In the framework of $SU(2)_L \otimes U(1)_Y$ effective Lagrangians, we examine all dimension--six operators that lead to anomalous Higgs interactions involving $\gamma$ and $Z$. The search for Higgs boson decaying to $\gamma\gamma$ pairs allow us to obtain constrains on these anomalous couplings that are comparable with the ones originating from the analyses of $p\bar{p}$ collisions at the Tevatron. Our results also show that if the coefficients of all ``blind'' operators are assumed to have same magnitude, the indirect constraints on the anomalous couplings obtained from this analyses, for Higgs masses $M_H \lesssim$ 140 GeV, are more restrictive than the ones coming from the $W^+W^-$ production.Comment: 14 pages Latex file using RevTeX, 3 figures as .eps file

Theoretical investigations of a highly mismatched interface: the case of SiC/Si(001)

Using first principles, classical potentials, and elasticity theory, we investigated the structure of a semiconductor/semiconductor interface with a high lattice mismatch, SiC/Si(001). Among several tested possible configurations, a heterostructure with (i) a misfit dislocation network pinned at the interface and (ii) reconstructed dislocation cores with a carbon substoichiometry is found to be the most stable one. The importance of the slab approximation in first-principles calculations is discussed and estimated by combining classical potential techniques and elasticity theory. For the most stable configuration, an estimate of the interface energy is given. Finally, the electronic structure is investigated and discussed in relation with the dislocation array structure. Interface states, localized in the heterostructure gap and located on dislocation cores, are identified

Investigation of physiological pulsatile flow in a model arterial stenosis using large-eddy and direct numerical simulations

Physiologicalpulsatileflow in a 3D model of arterialstenosis is investigated by using largeeddysimulation (LES) technique. The computational domain chosen is a simple channel with a biological type stenosis formed eccentrically on the top wall. The physiological pulsation is generated at the inlet using the first harmonic of the Fourier series of pressure pulse. In LES, the large scale flows are resolved fully while the unresolved subgrid scale (SGS) motions are modelled using a localized dynamic model. Due to the narrowing of artery the pulsatileflow becomes transition-to-turbulent in the downstream region of the stenosis, where a high level of turbulent fluctuations is achieved, and some detailed information about the nature of these fluctuations are revealed through the investigation of the turbulent energy spectra. Transition-to-turbulent of the pulsatileflow in the post stenosis is examined through the various numerical results such as velocity, streamlines, velocity vectors, vortices, wall pressure and shear stresses, turbulent kinetic energy, and pressure gradient. A comparison of the LES results with the coarse DNS are given for the Reynolds number of 2000 in terms of the mean pressure, wall shear stress as well as the turbulent characteristics. The results show that the shear stress at the upper wall is low just prior to the centre of the stenosis, while it is maximum in the throat of the stenosis. But, at the immediate post stenotic region, the wall shear stress takes the oscillating form which is quite harmful to the blood cells and vessels. In addition, the pressure drops at the throat of the stenosis where the re-circulated flow region is created due to the adverse pressure gradient. The maximum turbulent kinetic energy is located at the post stenosis with the presence of the inertial sub-range region of slope −5/3