Simultaneous splenectomy (SPX) is preferentially performed in living donor liver transplantation (LDLT) to modulate portal flow; increase postoperative platelet count, especially among those with hepatitis C virus (HCV) infection; and modulate the immunologic status in ABO-incompatible cases. The negative effects of the procedure, however, are not well established. Records of 395 LDLTs performed at our institution, including 169 (42.8%) patients with simultaneous SPX and 226 (57.2%) patients with spleen preservation, were reviewed with special reference to the simultaneous SPX cases. The most common indication for SPX was HCV-related disease (n = 114), followed by low preoperative platelet count (n = 52), and other reasons (n = 3). Simultaneous splenectomy did not increase the platelet count in the early postoperative period, but the incidence of reoperation for postoperative hemorrhage was increased, mainly at the SPX site, within the first week. In addition, the operative time, intraoperative blood loss, and incidence of lethal infectious disease were significantly higher in the SPX group, whereas the incidence of small-for-size syndrome was comparable between groups. Finally, SPX was an independent predictor for both postoperative hemorrhage (odds ratio [OR] = 2.451; 95% confidence interval [CI] = 1.285-4.815; P = 0.006) and lethal infectious complication (OR = 3.748; 95% CI = 1.148-14.001; P = 0.03). In conclusion, on the basis of the present findings, we do not recommend simultaneous SPX in LDLT. Liver Transplantation 22 1526-1535 2016 AASLD.

Defects in ion-implanted GaN and their annealing properties were studied by using monoenergetic positron beams. Doppler broadening spectra of the annihilation radiation and the positron lifetimes were measured for Si+, O+, and Be+-implanted GaN grown by the metal-organic chemical vapor deposition technique. First-principles calculations were also used to identify defect species introduced by the implantation. For as-implanted samples, the major defect species was identified as Ga vacancies and/or divacancies. An agglomeration of defects starts after annealing at 400 °C, and the defect profile shifted toward the surface with the open volumes of the defects increasing. The annealing properties of defects were found to depend on the ion species, and they are discussed here in terms of defect concentrations and interactions between impurities and defects.

We consider the discrete one-dimensional Schrödinger operatorand V is a self-adjoint operator on ℓ 2 (Z) with a decay property given by V extending to a compact operator from ℓ ∞,−β (Z) to ℓ 1,β (Z) for some β ≥ 1. We give a complete description of the solutions to Hx = 0, and Hx = 4x, x ∈ ℓ ∞,−β (Z). Using this description we give asymptotic expansions of the resolvent of H at the two thresholds 0 and 4. One of the main results is a precise correspondence between the solutions to Hx = 0 and the leading coefficients in the asymptotic expansion of the resolvent around 0. For the resolvent expansion we implement the expansion scheme of Jensen-Nenciu [4,5] in the full generality.

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We construct a time‐dependent scattering theory for Schrödinger operators on a manifold M with asymptotically conic structure. We use the two‐space scattering theory formalism, and a reference operator on a space of the form ℝ×∂M, where ∂M is the boundary of M at infinity. We prove the existence and the completeness of the wave operators, and show that our scattering matrix is equivalent to the absolute scattering matrix, which is defined in terms of the asymptotic expansion of generalized eigenfunctions. Our method is functional analytic, and we use no microlocal analysis in this paper.

In this paper we introduce a notion of scattering theory for the Laplace-Beltrami operator on non-compact, connected and complete Riemannian manifolds. A principal condition is given by a certain positive lower bound of the second fundamental form of angular submanifolds at infinity. Another condition is certain bounds of derivatives up to order one of the trace of this quantity. These conditions are shown to be optimal for existence and completeness of a wave operator. Our theory does not involve prescribed asymptotic behaviour of the metric at infinity (like asymptotic Euclidean or hyperbolic metrics studied previously in the literature). A consequence of the theory is spectral theory for the Laplace-Beltrami operator including identification of the continuous spectrum and absence of singular continuous spectrum.This work was essentially done during K.I.'s stay in Aarhus University (academic year 2009-2010). He would like to express his gratitude for financial support from FNU 160377 (2009from FNU 160377 ( -2011 as well as from JSPS Wakate (B) 21740090 (2009)(2010)(2011)(2012). E.S. thanks H.D. Cornean and I. Herbst for many preliminary discussions of scattering theory on manifolds [CHS2]. We thank H. Kumura for bringing our attention on his work [Ku2].

In this paper we study absence of embedded eigenvalues for Schrödinger operators on non-compact connected Riemannian manifolds. A principal example is given by a manifold with an end (possibly more than one) in which geodesic coordinates are naturally defined. In this case one of our geometric conditions is a positive lower bound of the second fundamental form of angular submanifolds at infinity inside the end. Another condition may be viewed (at least in a special case) as being a bound of the trace of this quantity, while similarly, a third one as being a bound of the derivative of this trace. In addition to geometric bounds we need conditions on the potential, a regularity property of the domain of the Schrödinger operator and the unique continuation property. Examples include ends endowed with asymptotic Euclidean or hyperbolic metrics studied previously in the literature.

Given a scattering metric on the Euclidean space. We consider the Schrödinger equation corresponding to the metric, and study the propagation of singularities for the solution in terms of the homogeneous wavefront set. We also prove that the notion of the homogeneous wavefront set is essentially equivalent to that of the quadratic scattering wavefront set introduced by J. Wunsch [21]. One of the main results in [21] follows on the Euclidean space with a weaker, almost optimal condition on the potential.