Reconstructing the Equation of State for Dark Energy In the Double Complex Symmetric Gravitational Theory

We propose to study the accelerating expansion of the universe in the double complex symmetric gravitational theory (DCSGT). The universe we live in is taken as the real part of the whole spacetime ${\cal M}^4_C(J)$ which is double complex. By introducing the spatially flat FRW metric, not only the double Friedmann Equations but also the two constraint conditions $p_J=0$ and $J^2=1$ are obtained. Furthermore, using parametric $D_L(z)$ ansatz, we reconstruct the $\omega^{'}(z)$ and $V(\phi)$ for dark energy from real observational data. We find that in the two cases of $J=i,p_J=0$ and $J=\epsilon,p_J\neq 0$, the corresponding equations of state $\omega^{'}(z)$ remain close to -1 at present ($z=0$) and change from below -1 to above -1. The results illustrate that the whole spacetime, i.e. the double complex spacetime ${\cal M}^4_C(J)$, may be either ordinary complex ($J=i,p_J=0$) or hyperbolic complex ($J=\epsilon,p_J\neq 0$). And the fate of the universe would be Big Rip in the future.Comment: 5 pages, 5 figures, accepted by Commun. Theor. Phy

A New Class of Inhomogeneous String Cosmological Models in General Relativity

A new class of solutions of Einstein field equations has been investigated for inhomogeneous cylindrically symmetric space-time with string source. To get the deterministic solution, it has been assumed that the expansion ($\theta$) in the model is proportional to the eigen value $\sigma^{1}_{1}$ of the shear tensor $\sigma^{i}_{j}$. Certain physical and geometric properties of the models are also discussed.Comment: 12 pages, no figure. Submitted to Astrophys. Space Sci. arXiv admin note: substantial text overlap with arXiv:0705.090

Temperature and heat stress of vessels during cold perfusion of kidney

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.The first step of organ cryopreservation is a cryoprotectant perfusion, which can speed cooling. The temperature of the kidney decreased from 37℃ to about 0℃ by perfusion. During the kidney perfusion process, the cryoprotectant enters the kidneys through the renal artery and leaves the kidneys through the renal vein after passing through a series of capillaries. In cold perfusion vessels with a diameter larger than 0.3 mm must be treated individually. The obvious temperature change in the larger vessels will bring in the displacement causing by the thermal contraction. This paper is dedicated to present a comprehensive investigation on the thermal effects of larger blood vessels during cold perfusion including temperature change and corresponding heat stress. A structural model of heat transfer in kidney is developed using currently available anatomical and physiological data. To characterize the effect of thermally significant blood vessels on heat transfer inside the tissues during cold perfusion, the cryoprotectant in the blood vessel was controlled by the energy equation and Navier-Stokes equations. The tiny capillaries and its surrounding biological tissue were treated as the porous media following Darcy's Law. The controlling equations were numerically solved by CFD software. The numerical simulation for the coupled transient thermal field and stress field is carried out by sequentially thermal-structural coupled method based on ANSYS to evaluate the stress fields and of deformations which are established in the blood vessel and tissue. The results indicated that the thermal effects of large blood vessels could remarkably affect the temperature distribution of cold perfusion. And the heat stress obvious changed during cooling, especially for the vein. The maximal heat stress occurred at the export of the vein. This position may be the keys to avoid stress injury during perfusion. This paper provides a guideline to optimize the cold perfusion process from the biomechanics effect.cf201

Enhanced iron and zinc accumulation in genetically engineered wheat plants using sickle alfalfa (Medicago falcata L.) ferritin gene

Iron deficiency is the most common nutritional disorder, affecting over 30% of the world’s human population. The primary method used to alleviate this problem is nutrient biofortification of crops so as to improve the iron content and its availability in food sources. The over-expression of ferritin is an effective method to increase iron concentration in transgenic crops. For the research reported herein, sickle alfalfa (Medicago falcata L.) ferritin was transformed into wheat driven by the seed-storage protein glutelin GluB-1 gene promoter. The integration of ferritin into the wheat was assessed by PCR, RT-PCR and Western blotting. The concentration of certain minerals in the transgenic wheat grain was determined by inductively coupled plasma-atomic emission spectrometry, the results showed that grain Fe and Zn concentration of transgenic wheat increased by 73% and 44% compared to nontransformed wheat, respectively. However, grain Cu and Cd concentration of transgenic wheat grain decreased significantly in comparison with non-transformed wheat. The results suggest that the over-expression of sickle alfalfa ferritin, controlled by the seed-storage protein glutelin GluB-1 gene promoter, increases the grain Fe and Zn concentration, but also affects the homeostasis of other minerals in transgenic wheat grain

Flux Creep and Flux Jumping

We consider the flux jump instability of the Bean's critical state arising in the flux creep regime in type-II superconductors. We find the flux jump field, $B_j$, that determines the superconducting state stability criterion. We calculate the dependence of $B_j$ on the external magnetic field ramp rate, $\dot B_e$. We demonstrate that under the conditions typical for most of the magnetization experiments the slope of the current-voltage curve in the flux creep regime determines the stability of the Bean's critical state, {\it i.e.}, the value of $B_j$. We show that a flux jump can be preceded by the magneto-thermal oscillations and find the frequency of these oscillations as a function of $\dot B_e$.Comment: 7 pages, ReVTeX, 2 figures attached as postscript file

Growth of High Quality CdZnTe Films by Close-Spaced Sublimation Method

AbstractThe effects of substrate temperature, source temperature and separation distance between the source and substrate on the growth rate of CdZnTe (CZT) films by Closed Space Sublimation (CSS) were systematically investigated. A maximum deposition rate of above 5μm/min was achieved with a source temperature of 650°C. The CZT films were heat treated by CdCl2 vapour in CSS system. The CdCl2 treatment on the structural and optical properties of CZT films was studied

Comments on gluon scattering amplitudes via AdS/CFT

In this article we consider n gluon color ordered, planar amplitudes in N=4 super Yang Mills at strong 't Hooft coupling. These amplitudes are approximated by classical surfaces in AdS_5 space. We compute the value of the amplitude for a particular kinematic configuration for a large number of gluons and find that the result disagrees with a recent guess for the exact value of the amplitude. Our results are still compatible with a possible relation between amplitudes and Wilson loops. In addition, we also give a prescription for computing processes involving local operators and asymptotic states with a fixed number of gluons. As a byproduct, we also obtain a string theory prescription for computing the dual of the ordinary Wilson loop, Tr P exp[ i\oint A ], with no couplings to the scalars. We also evaluate the quark-antiquark potential at two loops.Comment: 27 pages, 9 figures,v3:minor correction