11,399 research outputs found
Fateev-Zamolodchikov and Kashiwara-Miwa models: boundary star-triangle relations and surface critical properties
The boundary Boltzmann weights are found by solving the boundary
star-triangle relations for the Fateev-Zamolodchikov and Kashiwara-Miwa models.
We calculate the surface free energies of the models. The critical surface
exponent \alpha_s of the Kashiwara-Miwa model is given and satisfies the
scaling relation \alpha_b=2\alpha_s-2, where \alpha_b is the bulk exponent.Comment: 17 pages, no ps figures, latex fil
Fusion Hierarchy and Finite-Size Corrections of Invariant Vertex Models with Open Boundaries
The fused six-vertex models with open boundary conditions are studied. The
Bethe ansatz solution given by Sklyanin has been generalized to the transfer
matrices of the fused models. We have shown that the eigenvalues of transfer
matrices satisfy a group of functional relations, which are the (2) fusion
rule held by the transfer matrices of the fused models. The fused transfer
matrices form a commuting family and also commute with the quantum group
. In the case of the parameter () the
functional relations in the limit of spectral parameter u\to \i\infty are
truncated. This shows that the (2) fusion rule with finite level appears
for the six vertex model with the open boundary conditions. We have solved the
functional relations to obtain the finite-size corrections of the fused
transfer matrices for low-lying excitations. From the corrections the central
charges and conformal weights of underlying conformal field theory are
extracted. To see different boundary conditions we also have studied the
six-vertex model with a twisted boundary condition.Comment: Pages 29; revised versio
SOLUTION OF FUNCTIONAL EQUATIONS OF RESTRICTED FUSED LATTICE MODELS
Functional equations, in the form of fusion hierarchies, are studied for the
transfer matrices of the fused restricted lattice models of
Jimbo, Miwa and Okado. Specifically, these equations are solved analytically
for the finite-size scaling spectra, central charges and some conformal
weights. The results are obtained in terms of Rogers dilogarithm and correspond
to coset conformal field theories based on the affine Lie algebra
with GKO pair .Comment: 25 pages;latex file(epic.tex needed);Res.Rep.No 39;Tex Prob. fixed
Algebraic Bethe ansatz for the supersymmetric model with reflecting boundary conditions
In the framework of the graded quantum inverse scattering method (QISM), we
obtain the eigenvalues and eigenvectors of the supersymmetric model with
reflecting boundary conditions in FFB background. The corresponding Bethe
ansatz equations are obtained.Comment: Latex file, 23 Page
Surface Critical Phenomena and Scaling in the Eight-Vertex Model
We give a physical interpretation of the entries of the reflection
-matrices of Baxter's eight-vertex model in terms of an Ising interaction at
an open boundary. Although the model still defies an exact solution we
nevertheless obtain the exact surface free energy from a crossing-unitarity
relation. The singular part of the surface energy is described by the critical
exponents and , where controls the strength of the four-spin
interaction. These values reduce to the known Ising exponents at the decoupling
point and confirm the scaling relations
and .Comment: 12 pages, LaTeX with REVTEX macros needed. To appear in Physical
Review Letter
Visual characterization of associative quasitrivial nondecreasing operations on finite chains
In this paper we provide visual characterization of associative quasitrivial
nondecreasing operations on finite chains. We also provide a characterization
of bisymmetric quasitrivial nondecreasing binary operations on finite chains.
Finally, we estimate the number of functions belonging to the previous classes.Comment: 25 pages, 18 Figure
Two Magnetic Impurities with Arbitrary Spins in Open Boundary t-J Model
From the open boundary t-J model, an impurity model is constructed in which
magnetic impurities of arbitrary spins are coupled to the edges of the strongly
correlated electron system. The boundary R matrices are given explicitly. The
interaction parameters between magnetic impurities and electrons are related to
the potentials of the impurities to preserve the integrability of the system.
The Hamiltonian of the impurity model is diagonalized exactly. The integral
equations of the ground state are derived and the ground state properties are
discussed in details. We discuss also the string solutions of the Bethe ansatz
equations, which describe the bound states of the charges and spins. By
minimizing the thermodynamic potential we get the thermodynamic Bethe ansatz
equations. The finite size correction of the free energy contributed by the
magnetic impurities is obtained explicitly. The properties of the system at
some special limits are discussed and the boundary bound states are obtained.Comment: 18 pages, Revte
Solutions of the reflection equations for the vertex model
We investigate the possible regular solutions of the boundary Yang-Baxter
equation for the fundamental vertex model. We find four distinct
classes of reflection matrices such that half of them are diagonal while the
other half are non-diagonal. The latter are parameterized by two continuous
parameters but only one solution has all entries non-null. The non-diagonal
solutions do not reduce to diagonal ones at any special limit of the
free-parameters.Comment: 18 page
The density of macrophages in the invasive front is inversely correlated to liver metastasis in colon cancer
<p>Abstract</p> <p>Background</p> <p>Although an abundance of evidence has indicated that tumor-associated macrophages (TAMs) are associated with a favorable prognosis in patients with colon cancer, it is still unknown how TAMs exert a protective effect. This study examined whether TAMs are involved in hepatic metastasis of colon cancer.</p> <p>Materials and methods</p> <p>One hundred and sixty cases of pathologically-confirmed specimens were obtained from colon carcinoma patients with TNM stage IIIB and IV between January 1997 and July 2004 at the Cancer Center of Sun Yat-Sen University. The density of macrophages in the invasive front (CD68TF<sub>Hotspot</sub>) was scored with an immunohistochemical assay. The relationship between the CD68TF<sub>Hotspot </sub>and the clinicopathologic parameters, the potential of hepatic metastasis, and the 5-year survival rate were analyzed.</p> <p>Results</p> <p>TAMs were associated with the incidence of hepatic metastasis and the 5-year survival rate in patients with colon cancers. Both univariate and multivariate analyses revealed that the CD68TF<sub>Hotspot </sub>was independently prognostic of survival. A higher 5-year survival rate among patients with stage IIIB after radical resection occurred in patients with a higher macrophage infiltration in the invasive front (81.0%) than in those with a lower macrophage infiltration (48.6%). Most importantly, the CD68TF<sub>Hotspot </sub>was associated with both the potential of hepatic metastasis and the interval between colon resection and the occurrence of hepatic metastasis.</p> <p>Conclusion</p> <p>This study showed evidence that TAMs infiltrated in the invasive front are associated with improvement in both hepatic metastasis and overall survival in colon cancer, implying that TAMs have protective potential in colon cancers and might serve as a novel therapeutic target.</p
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