On the Logarithmic Asymptotics of the Sixth Painleve' Equation (Summer 2007)

We study the solutions of the sixth Painlev\'e equation with a logarithmic asymptotic behavior at a critical point. We compute the monodromy group associated to the solutions by the method of monodromy preserving deformations and we characterize the asymptotic behavior in terms of the monodromy itself.Comment: LaTeX with 8 figure

Movable algebraic singularities of second-order ordinary differential equations

Any nonlinear equation of the form y''=\sum_{n=0}^N a_n(z)y^n has a (generally branched) solution with leading order behaviour proportional to (z-z_0)^{-2/(N-1)} about a point z_0, where the coefficients a_n are analytic at z_0 and a_N(z_0)\ne 0. We consider the subclass of equations for which each possible leading order term of this form corresponds to a one-parameter family of solutions represented near z_0 by a Laurent series in fractional powers of z-z_0. For this class of equations we show that the only movable singularities that can be reached by analytic continuation along finite-length curves are of the algebraic type just described. This work generalizes previous results of S. Shimomura. The only other possible kind of movable singularity that might occur is an accumulation point of algebraic singularities that can be reached by analytic continuation along infinitely long paths ending at a finite point in the complex plane. This behaviour cannot occur for constant coefficient equations in the class considered. However, an example of R. A. Smith shows that such singularities do occur in solutions of a simple autonomous second-order differential equation outside the class we consider here

Nanoscale anisotropic structural correlations in the paramagnetic and ferromagnetic phases of Nd0.5Sr0.5 MnO3

We report x-ray scattering studies of short-range structural correlations and diffuse scattering in Nd0.5Sr0.5MnO3. On cooling, this material undergoes a series of transitions, first from a paramagnetic insulating (PI) to a ferromagnetic metallic (FM) phase, and then to a charge-ordered (CO) insulating state. Highly anisotropic structural correlations were found in both the PI and FM states. The correlations increase with decreasing temperature, reaching a maximum at the CO transition temperature. Below this temperature, they abruptly collapsed. Single-polaron diffuse scattering was also observed in both the PI and FM states suggesting that substantial local lattice distortions are present in these phases. We argue that our measurements indicate that nanoscale regions exhibiting layered orbital order exist in the paramagnetic and ferromagnetic phases of Nd0.5Sr0.5MnO3.Comment: 5 pages, 4 embedded figure

Elevation of soluble interleukin-2 receptor levels in nasal allergy

To investigate soluble IL-2 receptor (sIL-2R) levels in nasal allergy, the sera and nasal secretions from patients with nasal allergy and from healthy subjects were subjected to a double-epitope enzyme-linked immunosorbent assay. Significant elevation of sIL-2R concentrations in the sera and nasal secretions was observed in the allergy patients (n = 26) compared with those of healthy subjects (n = 9). IL-2R-positive (CD25+) cells were observed in the crust formed in an allergic nasal mucosa. The concentration of sIL-2R in the sera correlated neither with the eosinophil count of the peripheral blood count nor with clinical severity. The concentration of sIL-2R in the nasal secretions was significantly higher compared with that in the sera from allergic patients (p < 0.01), whereas no significant difference was observed between sIL-2R levels in the sera and nasal sections from normal subjects. These findings indicate that sIL-2R plays an essential role in allergic processes by regulating IL-2R-positive cells recruited into the nasal mucosa

Development of a ground displacement measurement method for failed slopes at the toes of landslides

International audienceSediments produced by a slope failure of the toe of a landslide are assumed to prevent the spread of the failure. Thus, sediment removal is an emergency measure that must be done safely while the slope is observed. Observation must also be done safely without requiring workers to enter the failed slope to avoid secondary disasters. Generally, a non-prism type totalstation is useful to measure ground displacement under such circumstances, because this type of totalstation can be used without placing targets on the slope. However, the lack of prisms results in problems related to the objectivity of measurement data, collimation error of the totalstation, measurement at night, and so on. The authors have developed targets and a remote target placing method in order to resolve the above problems. As a result, we have established remote measurement technique for ground displacement on failed slopes at the toes of landslides. This paper describes the measurement technique that has been developed

Frustration-induced Dodecamer Ordering in the Double-Exchange Spin Ice Model on the Kagom\'e Lattice

We investigate a detail of a dodecamer cluster ordering in a double-exchange spin ice model on a kagom\'e lattice. In frustrated systems, ordinary spin orderings are suppressed and macroscopic degeneracy remains down to low temperatures. In some frustrated systems, the degeneracy is lifted due to residual interactions and cluster orderings are stabilized. In the present model, the spin ice state is first formed at intermediate temperatures, and further entropies are released at lower temperatures as the dodecamer phase emerges. Since the spin symmetry is not broken in the dodecamer phase, there still exists macroscopic degeneracy. At further low temperatures, a possible spin ordering due to inter-dodecamer interactions is proposed. We discuss that such a multiple-site clustering larger than a bond-pair might be generic to frustrated systems where macroscopic degeneracy is lifted by residual interactions.Comment: 18 pages, 11 figure

Stripes Induced by Orbital Ordering in Layered Manganites

Spin-charge-orbital ordered structures in doped layered manganites are investigated using an orbital-degenerate double-exchange model tightly coupled to Jahn-Teller distortions. In the ferromagnetic phase, unexpected diagonal stripes at $x$=$1/m$ ($m$=integer) are observed, as in recent experiments. These stripes are induced by the orbital degree of freedom, which forms a staggered pattern in the background. A $\pi$-shift in the orbital order across stripes is identified, analogous to the $\pi$-shift in spin order across stripes in cuprates. At $x$=1/4 and 1/3, another non-magnetic phase with diagonal static charge stripes is stabilized at intermediate values of the $t_{\rm 2g}$-spins exchange coupling.Comment: reordering of figure

Hepatitis C virus quasispecies in cancerous and noncancerous hepatic lesions: the core protein-encoding region.

We have shown that highly proofreading DNA polymerase is required for the polymerase chain reaction in the genetic analysis of hepatitis C virus (HCV). To clarify the status of HCV quasispecies in hepatic tissue using proofreading DNA polymerase, we performed a genetic analysis of the HCV core protein-encoding region in cancerous and noncancerous lesions derived from 4 patients with hepatocellular carcinoma. In contrast to the previously published data, we observed neither deletions nor stop codons in the analyzed region and no significant difference in the complexity of HCV quasispecies between cancerous and noncancerous lesions. This result suggests that the HCV core gene is never structurally defective in hepatic tissues, including cancerous lesions. However, in 3 of the patients, the consensus HCV species differed between cancerous and noncancerous lesions, suggesting that the predominant replicating HCV species differs between these 2 types of lesions. Moreover, during the course of the study, we obtained several interesting variants possessing a substitution at codon 9 of the core gene, whose substitution has been shown to induce the production of the F protein synthesized by a - 2/+1 ribosomal frameshift.</p