Duality in Complex sine-Gordon Theory

New aspects of the complex sine-Gordon theory are addressed through the reformulation of the theory in terms of the gauged Wess-Zumino-Witten action. A dual transformation between the theory for the coupling constant \b > 0 and the theory for \b < 0 is given which agrees with the Krammers-Wannier duality in the context of perturbed conformal field theory. The B\"{a}cklund transform and the nonlinear superposition rule for the complex sine-Gordon theory are presented and from which, exact solutions, solitons and breathers with U(1) charge, are derived. We clarify topological and nontopological nature of neutral and charged solitons respectively, and discuss about the duality between the vector and the axial U(1) charges.Comment: 10 pages, LaTe

Deformed Minimal Models and Generalized Toda Theory

We introduce a generalization of $A_{r}$-type Toda theory based on a non-abelian group G, which we call the $(A_{r},G)$-Toda theory, and its affine extensions in terms of gauged Wess-Zumino-Witten actions with deformation terms. In particular, the affine $(A_{1},SU(2))$-Toda theory describes the integrable deformation of the minimal conformal theory for the critical Ising model by the operator $\Phi_{(2,1)}$. We derive infinite conserved charges and soliton solutions from the Lax pair of the affine $(A_{1}, SU(2))$-Toda theory. Another type of integrable deformation which accounts for the $\Phi_{(3,1)}$-deformation of the minimal model is also found in the gauged Wess-Zumino-Witten context and its infinite conserved charges are given.Comment: 11pages, SNUCTP 94-83 (One reference has been added.

Analytic study of the urn model for separation of sand

We present an analytic study of the urn model for separation of sand recently introduced by Lipowski and Droz (Phys. Rev. E 65, 031307 (2002)). We solve analytically the master equation and the first-passage problem. The analytic results confirm the numerical results obtained by Lipowski and Droz. We find that the stationary probability distribution and the shortest one among the characteristic times are governed by the same free energy. We also analytically derive the form of the critical probability distribution on the critical line, which supports their results obtained by numerically calculating Binder cumulants (cond-mat/0201472).Comment: 6 pages including 3 figures, RevTe

Path Integral Bosonization of Massive GNO Fermions

We show the quantum equivalence between certain symmetric space sine-Gordon models and the massive free fermions. In the massless limit, these fermions reduce to the free fermions introduced by Goddard, Nahm and Olive (GNO) in association with symmetric spaces $K/G$. A path integral formulation is given in terms of the Wess-Zumino-Witten action where the field variable $g$ takes value in the orthogonal, unitary, and symplectic representations of the group $G$ in the basis of the symmetric space. We show that, for example, such a path integral bosonization is possible when the symmetric spaces $K/G$ are $SU(N) \times SU(N)/SU(N); N \le 3, ~ Sp(2)/U(2)$ or $SO(8)/U(4)$. We also address the relation between massive GNO fermions and the nonabelian solitons, and explain the restriction imposed on the fermion mass matrix due to the integrability of the bosonic model.Comment: 11 page

Vortex String Dynamics in an External Antisymmetric Tensor Field

We study the Lund-Regge equation that governs the motion of strings in a constant background antisymmetric tensor field by using the duality between the Lund-Regge equation and the complex sine-Gordon equation. Similar to the cases of vortex filament configurations in fluid dynamics, we find various exact solitonic string configurations which are the analogue of the Kelvin wave, the Hasimoto soliton and the smoke ring. In particular, using the duality relation, we obtain a completely new type of configuration which corresponds to the breather of the complex sine-Gordon equation.Comment: 20 pages, 9 figure

Classical Matrix sine-Gordon Theory

The matrix sine-Gordon theory, a matrix generalization of the well-known sine-Gordon theory, is studied. In particular, the $A_{3}$-generalization where fields take value in $SU(2)$ describes integrable deformations of conformal field theory corresponding to the coset $SU(2) \times SU(2) /SU(2)$. Various classical aspects of the matrix sine-Gordon theory are addressed. We find exact solutions, solitons and breathers which generalize those of the sine-Gordon theory with internal degrees of freedom, by applying the Zakharov-Shabat dressing method and explain their physical properties. Infinite current conservation laws and the B\"{a}cklund transformation of the theory are obtained from the zero curvature formalism of the equation of motion. From the B\"{a}cklund transformation, we also derive exact solutions as well as a nonlinear superposition principle by making use of the Bianchi's permutability theorem.Comment: 25 pages, 6 Postscript figure

Conformal Turbulence with Boundary

Based upon the formalism of conformal field theory with a boundary, we give a description of the boundary effect on fully developed two dimensional turbulence. Exact one and two point velocity correlation functions and energy power spectrum confined in the upper half plane are obtained using the image method. This result enables us to address the infrared problem of the theory of conformal turbulence.Comment: 10pages, KHTP-93-01, SNUCTP-93-0

Analysis on dynamic tensile extrusion behavior of UFG OFHC Cu

Dynamic tensile extrusion (DTE) tests with the strain rate order of similar to 10(5) s(-1) were conducted on coarse grained (CG) Cu and ultrafine grained (UFG) Cu. ECAP of 16 passes with route B-c was employed to fabricate UFG Cu. DTE tests were carried out by launching the sphere samples to the conical extrusion die at a speed of similar to 475 m/sec in a vacuumed gas gun system. UFG Cu was fragmented into 3 pieces and showed a DTE elongation of similar to 340%. CG Cu exhibited a larger DTE elongation of similar to 490% with fragmentation of 4 pieces. During DTE tests, dynamic recrystallization occurred in UFG Cu, but not in CG Cu. In order to examine the DTE behavior of CG Cu and UFG Cu under very high strain rates, a numerical analysis was undertaken by using a commercial finite element code (LS-DYNA 2D axis-symmetric model) with the Johnson - Cook model. The numerical analysis correctly predicted fragmentation and DTE elongation of CG Cu. But, the experimental DTE elongation of UFG Cu was much smaller than that predicted by the numerical analysis. This difference is discussed in terms of microstructural evolution of UFG Cu during DTE tests.111Ysciescopu

JAK2V617F promotes replication fork stalling with disease-restricted impairment of the intra-S checkpoint response

Cancers result from the accumulation of genetic lesions, but the cellular consequences of driver mutations remain unclear, especially during the earliest stages of malignancy. The V617F mutation in the JAK2 non-receptor tyrosine kinase (JAK2V617F) is present as an early somatic event in most patients with myeloproliferative neoplasms (MPNs), and the study of these chronic myeloid malignancies provides an experimentally tractable approach to understanding early tumorigenesis. Introduction of exogenous JAK2V617F impairs replication fork progression and is associated with activation of the intra-S checkpoint, with both effects mediated by phosphatidylinositide 3-kinase (PI3K) signaling. Analysis of clonally derived JAK2V617F-positive erythroblasts from MPN patients also demonstrated impaired replication fork progression accompanied by increased levels of replication protein A (RPA)-containing foci. However, the associated intra-S checkpoint response was impaired in erythroblasts from polycythemia vera (PV) patients, but not in those from essential thrombocythemia (ET) patients. Moreover, inhibition of p53 in PV erythroblasts resulted in more gamma-H2Ax (γ-H2Ax)–marked double-stranded breaks compared with in like-treated ET erythroblasts, suggesting the defective intra-S checkpoint function seen in PV increases DNA damage in the context of attenuated p53 signaling. These results demonstrate oncogene-induced impairment of replication fork progression in primary cells from MPN patients, reveal unexpected disease-restricted differences in activation of the intra-S checkpoint, and have potential implications for the clonal evolution of malignancies

Luminescence Property of Rare-Earth Doped Bismuth-Borate Glasses

AbstractWe fabricated rare-earth doped bismuth borate glasses by using melt-quench technique. Two different types glass samples of xBi2O3: (100-x)B2O3 (x=30 and 50) were made to compare the luminescence properties. We measured x-ray luminescence of Bi-glass by using a x-ray tube. Several dopants were doped into the Bi-glass to measure the x-ray luminescence such as CeO2, Nd2O3, Er2O3, Dy2O3, Pr2O3, Sm2O3, Ho2O3, Gd2O3 and CeF3. Among them, Dy2O3, Nd2O3 and Sm2O3 doped Bi-glass emitted luminescence. We measured emission spectrum of each samples. Dy2O3 doped bi-glass has emission band at 482nm, 575nm, 662nm and 765nm. Nd2O3 doped bi-glass have emission band at 895nm and Sm2O3 doped Bi-glass has emission band at 569nm, 598nm, 641nm and 705nm. Moreover, Bi-glass scintillators with high light yield with good radiation hardness and low cost can be applied in high energy and nuclear physics, medical imaging, homeland security and radiation detection